Strategy in Industrial Networks:
Transcription
Strategy in Industrial Networks:
Strategy in Industrial Networks: EXPERIENCES FROM IKEA Enrico Baraldi I KEA was founded over 60 years ago in Southern Sweden. It has since grown to become the world’s largest furniture retailer; in 2006, it had sales of over Euro17 billion, as well as 12,000 product items and 104,000 employees. The company’s focus has consistently been on marketing products at extremely low prices. Its first purchases in the 1950s were made from producers’ unsold stocks, in order to keep costs low. However, large sales success soon allowed IKEA to start ordering models of its own design from local manufacturers. Next, IKEA introduced innovations, such as flat packs, which reduced production and transport costs, and the “showroom-warehouse” concept, which reduced retailing costs. During its expansion in the 1960s, IKEA also laid the groundwork for its purchasing strategy, relying on long-term relationships with selected suppliers as external sources for its offerings. Today, its supply network spans the entire world and has become increasingly complex. However, the use of this network is still in accordance with the same basic strategy as in the 1960s: to design and purchase products that entail low production and transportation costs. IKEA achieves this by carefully taking into account, in its design and purchase strategy, all the activities performed in the network, from raw materials to customer homes. Remaining faithful to its original external orientation, IKEA performs only a few of these activities internally, while it intensively uses its relationships with suppliers to combine its internal and their external resources for the sake of both efficiency and development. For instance, products are developed in close interaction with suppliers while taking into consideration the impact of the raw materials, components, and facilities involved, since all these resources entail The author would like to thank Jan Gardberg of IKEA and all other managers that kindly provided the empirical material for this article, and two anonymous reviewers for their insightful comments. CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 99 Strategy in Industrial Networks: Experiences from IKEA FIGURE 1. IKEA and Its Industrial Network IKEA’s Boundary IKEA Trading Offices (40) IKEA of Sweden IKEA Distribution Centers (26) IKEA Stores (220) Suppliers (1,300) Logistic Partners (500) Sub-suppliers (10,000) costs and have an impact on quality, design, and function. In fact, next to low costs, reasonable quality, appealing designs, and adequate product functionality are major goals for IKEA. These goals induce the company to promote a constant product and technical development, which contributes to its image as an innovative and fashion-oriented firm, but which depends heavily on the contribution of its entire network of suppliers. To cope with such tasks, IKEA needs advanced skills in marketing, retailing, logistics, purchasing, product development, and technologies. This need of competence is reflected by IKEA’s complex organization, which consists of over 550 business units specializing in these fields and spread over more than 50 countries. However, the complexity of IKEA’s organization is overshadowed by that of its industrial network (see Figure 1). This network includes 1,300 direct suppliers and about 10,000 sub-suppliers, spread over 60 countries. Over 220 IKEA Enrico Baraldi is an Associate Professor at stores are located in 30 countries including Uppsala STS Center and at the Department of Business Studies, Uppsala University, Sweden. Europe, Australia, the U.S., and China. <[email protected]> Between IKEA’s stores and suppliers stands a vital, but less visible part of IKEA’s network: its wholesale and logistic operations, comprising 26 Distribution Centers spread over 12 countries. Since IKEA does not own any transport facilities, this network is physically connected via another group of external actors, a few hundred logistic partners. A pivotal role in this network is played by “IKEA of Sweden,” a leading business unit that not only manages IKEA’s product range, but also supervises the entire IKEA universe and develops long-term marketing, logistics, and purchas- 100 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA ing strategies. In fact, whereas most IKEA units are rather specialized (e.g., local purchasing for IKEA’s 40 Trading Offices), IKEA of Sweden has both an overall responsibility and a coordinating role in the development, purchase, distribution, and marketing of each single product. This article analyzes the experience of IKEA in dealing with its industrial network and discusses the structural components and dynamic interactions of a “network strategy,” that is, a strategy that considers and uses the external network for a company’s goals. The case study was built through 70 interviews, conducted mainly in 1999-2003 with personnel at IKEA and suppliers in Sweden, Poland, and Italy.1 The Pervasiveness of Industrial Networks Networks are widely publicized and researched phenomena, especially in high-tech sectors,2 where the likes of Dell, Microsoft, or Genentech pursue their network strategies through R&D joint ventures, cross-licensing, or strategic alliances. However, these fashionable terms do not fit the type of networking going on within the furniture industry or other low-tech industries. However, traditional sectors also present network-like structures. Examples include the tile industry,3 the apparel industry,4 and the Italian districts5—which specialize, for instance, in knitwear (Carpi), packaging machines (Bologna), or textiles (Prato). These sectors are composed of many small and medium-sized firms that develop close links to their suppliers and partners, and often also cooperate intensively with them on technical issues. Networks are not only important for small firms that need to interact with their peers to supplement their limited resources, but networks are fundamental for large companies as well. For instance, multinationals in the steel,6 paper,7 and automotive8 industries interact tightly with their suppliers, sub-suppliers, distributors, and customers to develop new technologies or increase efficiency. There are many examples of large firms from several sectors that relied strongly on networks for their rapid growth: Apple, Benetton, Toyota, Corning, and McDonald’s, to name a few.9 Finally, networks of stable relationships are the norm in several industries, including construction, publishing, textiles, and cultural production.10 It seems that all types of firms, large or small, high-tech or low-tech, interact closely with other firms and organizations around them. In other words, inter-firm interactions and networks are everywhere in our economy.11 However, despite all this interaction, inter-firm networks went practically unnoticed by mainstream management research until around the 1980s. This neglect of interfirm relationships stems from both the actual behavior of firms—in periods characterized by arm’s-length relations,12 close interactions and networks are more difficult to discern—and the dominant research paradigms, which either had different units of analysis or viewed relationships simply as odd exceptions.13 Although Richardson14 recognized the importance of business relationships as early as 1972, it took time for these ideas to enter mainstream strategy CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 101 Strategy in Industrial Networks: Experiences from IKEA literature; and when this finally happened, the impetus came from sociology. Granovetter stressed in 1985 that economic transactions are embedded in networks of social relations where trust matters,15 and Powell attributed networks a status equal to markets and hierarchies, viewed as three alternative forms for organizing economic activity.16 Eventually, Swedberg suggested that all markets can be viewed as social structures filled with interactions, rather than as pure price-driven mechanisms.17 In sum, there exists compelling evidence for the diffusion and persistence of business relationships and networks, in all sectors and for all sizes of firms. Mainstream strategy research was late in recognizing the importance of networks, and did not take them into account until the influence of sociology and widely publicized strategic alliances or joint ventures made it impossible to neglect this interactive side of business life. However, there is still a risk that focusing on these special and conspicuous networking episodes may hide the bulk of networking activities and interactions that go on silently under the surface of daily business activity.18 To avoid such a risk, one can rely on a theoretical perspective that views industrial networks and relationships as essential phenomena, that is, as the norm rather than the exception: this is the viewpoint of the “Markets-as-Networks” approach. “Markets-as-Networks”: A Network-Based View of Business Management Are we really sure that inter-firm relationships and networks are merely exceptions in economic organizing, in a world where firms can only choose between pure market exchanges or hierarchical control? What happens if we overstate the argument of Swedberg and start considering instead networks as the norm, that is, as the most natural and normal form of economic organizing?19 Following this reasoning, networks came first, while markets and hierarchies are both human constructions, that is, structures imposed on networks for the sake of transparency (markets) or control (hierarchies).20 Accepting networks as the norm can also help focus on the effects that they produce. Examples of such “network effects” are unexpected product failures,21 irrational patterns of electricity consumption,22 and imbalances spread by IT systems.23 However, to enable researchers and managers make sense of networks and their effects, appropriate analytical tools are necessary. A set of such tools for analyzing industrial networks as pervasive and “normal” phenomena is offered by a research tradition known as “IMP” (Industrial Marketing and Purchasing).24 This approach, sometimes referred to as “Markets-as-Networks,” grew out of extensive empirical studies of industrial buyer and seller relationships conducted in Europe in the 1960s and 1970s, that is, well before the modern frenzy over networks.25 The early empirical findings were then related to sociological theories of exchange26 in order to develop a series of models of the dyadic interaction between firms. These models stressed the importance of power/dependence, cooperation, closeness, and expectations in the daily interactions between buyer and seller.27 It was only a short step from 102 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA TABLE 1. The Structural Components and the Dynamic Interactions of a Network Strategy Structural Components Dynamic Interactions 1. Defining Relationship Contents: Contents include exchanged volumes, learning, trust, commitment, duration, and control (depending on a relationship’s goals, role and function). Combining Resources: Concrete and complex resource combinations created through interaction processes with external actors: inter-organizational routines/joint projects 2. Forming the Network Structure: This structure is based on the number of business relationships, their roles in the network, hierarchy, and geographical location. 1. Interacting via Inter-Organizational Routines: Repetitive and formal processes that mobilize relationships and enable resource combinations to maintain efficiency. 3. Evaluating Goal Matching with the Network: Comparing a firm’s goals/resources with those of the network.Which external resources are needed and available? What are the goals of other actors? 2. Interacting via Joint Projects: Ad hoc and informal processes that mobilize relationships and enable resources combinations to foster development. single relationships to networks of relationships: when IMP researchers recognized that single relationships are related to each other via technical, economic, and social interdependencies, the way was paved for more complex models stretching to the entire network surrounding a firm.28 The Markets-as-Networks approach has gained currency within the field of industrial marketing29 and international business,30 but it can also be used to cast new light on strategic issues of efficiency and development.31 To summarize, the Markets-as-Networks approach focuses on all types of inter-firm interactions. The starting point is that firms constantly interact with counterparts such as key suppliers and customers through business relationships that are related in a network structure. Consequently, firms are embedded within networks that exist beyond their will. From a strategic point of view, firms need to be aware of these networks and of how to use them actively. Companies vary widely in their will and capacity to do this: not all firms can become “strategic centers,” which, like IKEA, are able to manage a web of partners.32 Nevertheless, all firms are embedded in a network, which can be both good and bad.33 It is therefore advisable for firms to understand how networks work and how they can be approached for strategic purposes. The Structure and Dynamics of a Network Strategy A network strategy can be understood in terms of structures and dynamics, according to the idea that a network structure composed of relationships and external resources needs to emerge before a company can use the network in its daily interactions with counterparts. Therefore, the analytical frame that we will apply to discuss IKEA’s network strategy comprises three structural components and two types of dynamic interactions (see Table 1). The structural components concern the architecture of the network (e.g., the number of firms involved), the long-term features of each business relationship (e.g., the goals of the CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 103 Strategy in Industrial Networks: Experiences from IKEA involved actors), and the configuration of external resources (e.g., their distribution and technical connections). These structural elements are relatively stable and do not change overnight in a network, as stressed by the Markets-as-Networks approach.34 The dynamic interactions concern instead the processes that go on daily in any business relationship in terms of the activities performed, the communications among actors, and the concrete combinations and adaptations of resources across organizational boundaries. These interactions are termed “dynamic” because the underlying processes change more frequently and can contribute to changes in the structural components (e.g., to the emergence of new long-term goals or to the inclusion of new actors in the network structure). The three structural components are: definition of the content of each business relationship; formation of the network structure; and evaluation of the matching of IKEA’s goals and resources with those of the network. The logic of Component 1 is that IKEA strives to influence such relationship contents as exchanged volumes, commitments, trust and learning depending on how each relationship can contribute to achieving IKEA’s goals. However, Component 2 stresses that focusing on a single relationship would not be enough because IKEA’s goals can be reached only by connecting several relationships into a broader network structure, including the establishment of new relationships and the assignment of specific roles to certain counterparts within a hierarchy of relationships. Finally, Component 3 suggests that a firm needs to evaluate how its own goals and resources can match those of its counterparts in the network: unless this match can be achieved by means of dynamic interactions, adjustments might be necessary in the other two structural components, such as establishing new relationships or changing their contents. The three structural components provide the basic network structure within which dynamic interactions unfold continuously. At a general level, these daily interaction processes entail combinations of resources by IKEA and other actors in the attempt to match IKEA’s goals and resources with those in the network. At a specific level, there are two types of dynamic interactions: interacting via inter-organizational routines for efficiency purposes; and interacting via joint projects for development purposes. Whereas inter-organizational routines are, for efficiency’s sake, rigid scripts executed repetitively, joint projects are development processes that can stretch over several years, thus becoming less controllable by IKEA and more uncertain. IKEA,The Interacting Company: Handling a Network of Relationships IKEA’s relationships and network are pivotal in fostering development of IKEA’s products and technologies, and in sustaining efficiency in its daily operations. IKEA is certainly not the only firm that relies on extensive network interactions for its strategy. In particular, other retailing firms such as Benetton and Hennes & Mauritz apply a similar approach to complex webs of partners. However, IKEA does it in a special way. A major difference in comparison, for 104 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA instance, with Wal-Mart,35 is that IKEA stretches its interactions as far upstream as possible in the network, all the way to raw material suppliers. IKEA intensively cooperates with these suppliers in order to ensure the quality and the environmental friendliness of inputs to its direct suppliers downstream. Another important difference is the extent of IKEA’s cooperation with its partners: this extends to complex and enduring development projects whereby IKEA’s products and technologies are co-developed with suppliers.36 Finally, IKEA’s interaction mechanisms strongly differ from both hierarchically steered networks, such as the Japanese Keiretsu,37 and looser arm’slength relations mostly based on purchase power, such as those of Wal-Mart.38 The main difference is that instead of solely exploiting the power of being a large buyer, IKEA takes a long-term approach and strives to build lasting relationships based on mutuality. This means that it also explicitly considers the interests of suppliers, who would otherwise lose the motivation to interact with IKEA. Moreover, IKEA does not strive to unilaterally control these relationships, but relies on extensive delegation of tasks to its suppliers, and even accepts being dependent on some of them. Thus, for IKEA, mutual trust and commitment are more important interaction mechanisms than power. IKEA’s Background and the Structure of Its Network IKEA’s concern with providing low-price products characterizes both its current strategy and its history. The introduction of flat packs in the 1950s allowed important savings in transportation and production costs. In fact, IKEA’s customers took over assembly activities, and suppliers only needed to deliver un-assembled furniture components. Later on, selling costs could be contained thanks to “showroom-warehouses”: retail stores were redesigned so as to combine a large exhibition area with an adjacent self-service warehouse. IKEA could afford such low retail prices that its sales rocketed in the 1960s, signaling the start of its expansion, with several stores in Sweden and abroad. However, a strong reaction soon followed from Swedish furniture retailers, who tried to strangle IKEA’s purchase sources by requiring that all Swedish producers stopped supplying IKEA. IKEA’s countermove was to go looking for suppliers abroad. Thus, the first agreements with Polish producers were signed in the 1960s, laying the groundwork for many business relationships that still exist today. Long-lasting relationships with selected key suppliers are still the hallmark of IKEA’s purchasing and product development strategy. As IKEA is directly involved only in conceiving, distributing, and selling its products, it needs partners that can concretely develop and produce a total of 12,000 items that meet its cost, quality, and design goals. Still, extensive knowledge of the network, from raw materials to customer homes, is pivotal for IKEA to conceive products that are not only “cool” and functional enough to sell, but that can also be produced according to set cost and quality goals. Figure 1 gave a simplified idea of the extension and complexity of IKEA’s network, encompassing about 10,000 organizations, from sub-suppliers to IKEA retail stores. Connecting this network geographically requires a very advanced CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 105 Strategy in Industrial Networks: Experiences from IKEA logistic system, including 20,000 transport corridors. However, what counts more than these physical connections are the organizational connections that IKEA needs in order to interface with this complex network. In fact, IKEA created specific organizational interfaces to handle relationships with the various actors: not only the 1,300 direct suppliers and 500 carriers, but also hundreds of the 10,000 sub-suppliers, especially large firms supplying core materials such as packaging (e.g., SCA) or coatings (e.g., Akzo-Nobel). The strategic role of the unit known as IKEA of Sweden has already been mentioned. From IKEA’s hometown of Älmhult, its 700 employees perform another fundamental role: interacting from a central position with key logistic partners and suppliers on such strategic issues as long-term capacity planning and major technical development projects. Conversely, at a local level, the main interfaces with suppliers are IKEA’s 40 Trading Offices, employing 3,000 people worldwide. Even if these local purchasing offices replicate the structure and competence of the central unit, IKEA of Sweden (with purchase strategists, product category specialists, technicians, order managers, and logisticians), their interactions with suppliers mostly concern daily issues (e.g., orders and deliveries) and occasionally development or tendering for new product assignments. IKEA pays its Trading Offices a percentage on the purchases made from the suppliers they “represent.” Finally, the daily logistic coordination with all suppliers and carriers is handled by IKEA’s 26 Distribution Centers. IKEA’s Approach to Business Relationships IKEA’s approach to supplier relationships depends on the product involved. Complex products, both in terms of construction (e.g., sofas) and of production technology (e.g., the “Lack” table, featured below), are assigned to suppliers with which extensive mutual trust, commitment, and knowledge have been established through long-term relationships. These strong relationships entail extensive joint investments in facilities. On the other hand, products whose technical simplicity means they are easily interchangeable (e.g., rugs) are usually purchased through shorter-term relations. A similar variation exists in the relationships with logistic partners: out of over 500 such partners, IKEA has developed close cooperation with only 50 (e.g., Maersk, Willy Betz, SJ Cargo, and TNT), which between them account for 80% of IKEA’s transport volumes. Still, the majority of IKEA’s purchases happen through deep and established relationships. A common trait is IKEA’s attempt to avoid abusing its power position. The focus is instead on the mutual benefits accruing to both IKEA and its suppliers. Cooperation with IKEA should ideally bring suppliers advantages such as stable and long-term orders or technical development projects where IKEA can “pay” for thousands of tests. In fact, IKEA is well aware that those actors that no longer have advantages may end their cooperation (as did the coating supplier Becker-Acroma in the episode reviewed in Appendix A). Moreover, IKEA does not unilaterally control these relationships but accepts that it may sometimes be strongly dependent on its suppliers, as in the case of key logistic partners and those suppliers that daily refill IKEA’s stores 106 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA through “Vendor-Managed Inventory.” IKEA does not even unilaterally control such key sources of its innovativeness as product and technology development projects. Here, IKEA delegates much responsibility to the most competent partners, either those who have long been in charge of manufacturing a certain product, or those who have specific technical competences. Different Types of Relationships in IKEA’s Network The composition of IKEA’s network varies greatly in terms of the size of the actors involved. There are many small suppliers (and especially sub-suppliers) that are highly dependent on IKEA, and which IKEA can more directly influence with its powerful position. However, IKEA exerts its influence not only by holding down prices, but also by inducing suppliers to upgrade their technologies in ways that eventually benefit the suppliers themselves. This mutuality is in fact the hallmark of all of IKEA’s business relationships, even of those where IKEA could exploit a power position due to the overdependence of a supplier. On the other hand, there are also larger counterparts with which IKEA has a much more balanced power relation. These large actors are not easily influenced by IKEA, and they comply with IKEA’s requests only if they gain something from a specific cooperation. For instance, Akzo-Nobel, a sub-supplier of coatings, is a 15,000 employee and €6 billion chemical group. IKEA is certainly an important customer for Akzo-Nobel, but not to the extent that Akzo will blindly comply with any requests. Instead, Akzo-Nobel chooses to engage in IKEA’s development efforts when this provides it with specific advantages, such as learning a new technology. Similarly, the key logistic partner Maersk has thousands of trucks and employees, alongside hundreds of vessels and local offices: in this case, it is more IKEA’s transportation routines that need to fit into the logistic network of this partner rather than vice versa. Relationships with such large actors directly involve IKEA of Sweden for central negotiations; and even if IKEA still remains a key account for most suppliers (covering at least 1% of their sales), there is more balance in power and dependence. IKEA’s relationships are also very heterogeneous from a geographic point of view,39 because they are spread over the regions that provide specific resources or location advantages, such as nearness to IKEA’s major markets (Germany and Central Europe). Geographical location is one of the key factors when selecting new suppliers, because it strongly affects costs, competences, and delivery times. The resulting geographic pattern is as follows: Chinese suppliers rank first, with nearly 20% of purchase volumes, mainly due to cost reasons; Polish ones rank second, thanks to a good mix of low costs, technical competence, and nearness to Central Europe; and Swedish suppliers, despite high costs, still rank third thanks to their advanced technical competence. Geography is an important factor, but not the only factor, in supplier selection and hence in constructing the structure of IKEA’s network. During the selection process, IKEA of Sweden and the local Trading Offices that propose a supplier also evaluate these other factors, in order of importance: total costs, CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 107 Strategy in Industrial Networks: Experiences from IKEA provided that IKEA’s quality and environment requirements are respected; current and planned production capacity; technical competence; and readiness to make investments for and with IKEA. An additional rule is that suppliers should not depend on IKEA for more than 50% of their turnover. The rationale here is not only the avoidance of over-dependent suppliers that would be hurt too much if IKEA’s order volumes should decrease, but also reliance on the learning and development achieved by a supplier thanks to interactions with customers other than IKEA. Then, with some suppliers, IKEA develops long-lasting and complexcontent relationships, which entail large volumes and commitments. IKEA often even purchases machinery for these suppliers and trains their personnel. An even more restricted group of highly trusted suppliers is then invited to take part in complex technical development projects with IKEA: these suppliers are those with greater competences (e.g., in logistics or coating technologies) and those willing to become more committed to IKEA due to a positive history of interactions or strong expected benefits. IKEA already understood in the 1960s that using a long-term approach to purchasing actually favors IKEA itself, by allowing lower production costs and purchase prices and faster and improved development for its products. This approach produces even better results if IKEA follows a philosophy of mutuality and also takes into account the interests of its suppliers: this is reflected in IKEA’s attempt to balance production volumes among several suppliers and in IKEA’s investment programs to upgrade a supplier’s competences (e.g., technical or administrative training). For instance, IKEA applies a ladder model to IT and supplier logistics issues (see Figure 2): increasing supplier responsibility in deliveries (from simple fulfillment of IKEA’s orders to “Vendor-Managed Inventory”) must correspond both to increased IT integration with IKEA and to improved logistics capabilities. However, this model does not build only on improved routines and IT, but also on the development of a stronger business relationship, entailing more trust and commitment between IKEA and a supplier. This also implies better information flow and the commitment of concrete resources, ranging from dedicated personnel to building new warehouses at a supplier’s site. The deepening of a supplier relationship around IT and delivery issues starts from consistent delivery performances, and proceeds along a supplier’s improvements on these dimensions: ▪ increased experience of IKEA’s ordering routines or retail sales patterns; ▪ logisticians and order management teams dedicated to handling IKEA’s orders; ▪ improved communication with IKEA’s units such as retail stores and IKEA of Sweden; ▪ improved IT competences acquired from daily use of advanced IT tools such as ERPs; ▪ the willingness to invest in expensive new IT solutions; ▪ a direct knowledge of the IT ordering systems located at IKEA; and 108 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA FIGURE 2. IKEA’s Ladder Model for Supplier Interactions and IT/Logistics Capabilities VMI (Vendor-Managed Inventory) OPDC (Order-Point Distribution Center) Capability Requirements: (1% of suppliers qualify: trustworthy and proactive) Call-Off • Same as OPDC, plus… Capability Requirements: (almost 30% of supplies) Capability Requirements: (entry step: all suppliers) • delivery precision enough to fulfil only 13 orders per year within 4 weeks; • simple IT connection via nononline system ECIS (Electronic Commerce for IKEA Suppliers); • no need to be sole item supplier in the DC area. • increased delivery precision to fulfil daily orders within 12 days; • high production flexibility expanded warehousing facilities; • IKEA-dedicated order managers team, • online EDI-ERP connection with IKEA’s order system INOS; • need to be sole item supplier in the DC area. • highest delivery precision; • ability to manage IKEA stores’ inventories; • forecast retail sales; • set security stock levels; • plan/organize transport; • interact with all IKEA distribution units and with IKEA of Sweden for planned sales campaigns • deep knowledge of IKEA IT systems for inventory, ordering, and transport • direct online access to all the above IT systems. Key: Call-Off: IKEA emits orders every fourth week and suppliers must deliver within the next 4 weeks. OPDC: IKEA emits orders daily and suppliers must deliver within 12 days. VMI: Suppliers are in charge of deciding when and how much to deliver to IKEA. ▪ improved manufacturing flexibility and willingness to make physical investments (in production or warehousing capacity) in order to cope with fluctuating order volumes. Suppliers who achieve the aforementioned capabilities (often thanks to support and training provided by IKEA) and make the required commitments can move up along the ladder depicted in Figure 2. However, IKEA is also costdriven and a highly demanding customer that puts pressure on its suppliers. Therefore, if repeated efforts to improve a supplier competence and efficiency do not produce good results, IKEA is ready to terminate that relationship. As a result of IKEA’s efforts to develop (or terminate) supplier relationships, its CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 109 Strategy in Industrial Networks: Experiences from IKEA network is heterogeneous, a feature that IKEA views as a key source of development. What Goes on in IKEA’s Network? Two Interaction Processes The rich structure of relationships and the widespread competences accessed by IKEA through its network would be useless if IKEA did not have the ability to combine these resources to achieve efficiency and foster development. At a general level, this ability relies on IKEA’s organizational structure, on its strong competence in such areas as product and technology development or logistics, and on its long-term approach and network-oriented culture. At a more concrete level, the combination of external resources and competences relies on two managerial tools: detailed routines performed repetitively by IKEA and its suppliers in such efficiency-driving processes as order management; and ad hoc projects that tackle specific product and technical development issues and often involve up to 20 firms. Inter-organizational routines and projects are essential mechanisms to promote and handle the numerous interaction processes unfolding in the network structure reviewed above. Order Management Routines at IKEA and Its Partners This process defines the replenishment needs of IKEA stores and communicates them to the supplier in charge of each specific product. Setting exact order quantities is critical in order to avoid stock-outs in retail stores or extra inventory costs. Timing is essential too, because suppliers are bound to given lead-times and cannot react to a delayed order with immediate deliveries. IKEA achieves efficiency in the order-management process through an advanced procedure that estimates its own replenishment needs and very structured routines that transfer these needs to each supplier, stating such details as the exact response time and modes required from them. Nothing is left to chance, and IKEA considers many variables (such as stock levels, lead-times, and goods-intransit) to define when and how much should be ordered of a certain product. However, matters are complicated by the fact that IKEA sells 12,000 products, with very different production approaches and lead-times. For instance, a sofa will be finished after a customer order is placed, because the producer needs to wait until the customer has chosen the fabric; whereas standard products such as coffee tables are produced before orders, against sales forecasts. Therefore, IKEA’s orders of sofas and other customized products are steered by endcustomer orders, and so need longer lead-times; whereas orders of standard products are triggered by automatically preset reorder points at IKEA stores and Distribution Centers, and have shorter lead-times. To be able to fulfill an order, a supplier needs to master the details of the ordering routine specific to each of the products it delivers to IKEA. Manufacturers supplying IKEA with volumes higher than Euro50 million yearly have large teams of IKEA-dedicated order managers, fully engaged in handling IKEA’s orders. To further complicate things, not all IKEA suppliers are equally able to respect short lead-times and to fulfill orders coming in daily. Therefore, different 110 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA suppliers interact with IKEA by means of different ordering routines, depending on their ability and type of product. For instance, IKEA cannot implement with all suppliers the ordering routine “OPDC” (Order-Point Distribution Center), which involves issuing orders every day and requiring fulfillment within 12 days. Instead, many suppliers follow the “Call-Off” routine, which involves issuing orders every fourth week and requiring deliveries within the following 4 weeks. The OPDC modality is clearly more precise for IKEA’s receiving units and reduces stock levels and goods-in-transit within IKEA. However, OPDC creates stronger pressures on suppliers not only to learn a new ordering routine, but also to become more flexible and speculative, or even to increase finished goods stocks in order to react to shorter lead-times. Still, OPDC is not IKEA’s most demanding ordering routine for a supplier. The “VMI” routine (Vendor-Managed Inventory) grants suppliers access to IKEA’s stock data and assigns them the responsibility to decide when and how much to deliver. In this way, a supplier is empowered to exploit its knowledge of IKEA’s ordering patterns. However, this knowledge, essential to forecasting IKEA’s needs, only comes after having interacted daily with IKEA for some years. Additionally, with VMI, close interaction and joint planning between a supplier and IKEA stores become necessary to secure product coverage for special events such as store openings and sales promotions. All order management modalities are highly interactive routines performed daily by IKEA and its suppliers according to rigid scripts, mostly decided unilaterally by IKEA. At the same time, IKEA strives to introduce new ordering routines such as OPDC with key suppliers, according to the aforementioned ladder model that requires direct supplier involvement and large mutual investments. The “Printed Veneer” Project for the “Lack” Table An important type of development projects in IKEA’s network concerns new technologies. In fact, IKEA searches constantly for technologies that can reduce costs, improve quality, or allow new designs. Coating technology, for instance, is pivotal in furniture manufacturing, because it strongly affects both design and quality, but it is also costly and, if badly handled, can become hazardous to health. IKEA is therefore very concerned with coating technologies and has promoted hundreds of projects to improve them at its suppliers. One of these projects is the “printed veneer” project, which addressed the high cost of the veneers used for IKEA’s best-selling “Lack” table, with more than 2.5 million units sold yearly. In 2000, IKEA of Sweden raised some concerns about the high cost of veneers, which accounted for about 20% of the material costs for the veneered versions of Lack. These concerns triggered a series of discussions and an evaluation of potential solutions at Swedwood Poland, the manufacturer of Lack tables. Akzo-Nobel, one of their major coating suppliers, proposed to Swedwood a new coating technology that would allow substituting real veneers with a printed pattern. Thus, Swedwood and Akzo-Nobel initiated a large technology development project with the aim of printing veneer on wood. This project was particu- CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 111 Strategy in Industrial Networks: Experiences from IKEA FIGURE 3. The Network of Resources Combined in the “Printed Veneer” Project IKEA IKEA of Sweden HDF Swedwood Coating Line "Lack" Coatings/Inks Bürkle Sorbini Akzo-Nobel Product Business Unit Equipment Business Relationship larly important not only for cost reduction, but also for product design and aesthetics. Veneers are very visible on Lack tables and so the need to respect the perceived-quality requirements made this project particularly complex. The aesthetic target was that consumers should not notice any major difference in the printed pattern compared to real veneers. Akzo-Nobel took a leading role in perfecting the technology and introducing it into Swedwood’s plants. Leading the project meant identifying suppliers of the necessary equipment and supervising the many tests required to fine-tune the technical solution. Many technical and organizational resources had to be combined during this project (see Figure 3, which shows the products, equipment, business units, and relationships that were involved). The involved business units were all related by long-term relationships. In particular, Akzo had been supplying Swedwood for 20 years and closely interacted with IKEA of Sweden to negotiate the prices and conditions applicable to IKEA’s direct suppliers. Finding a way to print veneer patterns on Lack’s surface, which is made of HDF (high-density fiberboard), was not a technically easy task. 112 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA To start with, Akzo had to develop new coatings and inks. Moreover, many technical resources fell outside Akzo’s competence: new coating lines, resembling printing presses instead of traditional coaters, were necessary. Therefore, Bürkle and Sorbini, two coating lines suppliers who had previously supplied Swedwood and cooperated with Akzo, modified their equipment to suit the new process. Following Akzo and Swedwood’s specifications, Bürkle and Sorbini adapted two coating lines that were installed at Swedwood’s plants. However, the most demanding part of the project was getting all the technical resources to work together to satisfy IKEA’s requirements. This took over a year of tests, led by Akzo at Swedwood’s plants. On several occasions, Akzo had to modify its coatings and inks to allow them to work together with HDF and the new coating lines. However, by the time the new “print-on-wood” technology was ready, the problem of high-cost veneers had already been solved by a large supply of inexpensive and high-quality veneers purchased by IKEA’s Trading Offices. Still, the new technology was now available, and IKEA decided to apply it to other products manufactured by Swedwood, namely, a series of shelves that were officially launched in 2002. In initiating this project, IKEA had justified its high costs with large cost savings for a specific large-volume product, the Lack table. When the new technology became less relevant for these tables, IKEA could rely on the fact that Swedwood manufactured several other IKEA products with similar veneering problems. At the same time, efforts continue now to diffuse the “print-on-wood” technology both to other IKEA products and to other suppliers across IKEA’s network. Moreover, in 2006 the aforementioned large supply of inexpensive veneers dried out. Thus, printed veneer was finally applied to its original target, Lack tables. IKEA and Swedwood are currently discussing the application of the “print-on-wood” technology not only to substitute veneers, but also to print directly on IKEA’s furniture any pattern developed by IKEA’s designers. Thus, a technical development initiated for cost reduction has opened up another way to sustain IKEA’s image as an innovative and cool furniture company. Interaction processes such as ordering routines and the printed veneer project would not be possible without two important premises: IKEA’s internal structure and competences and its well developed interfaces for interacting with the network. For instance, IKEA of Sweden employs 700 people specializing in furniture technologies, logistics, and so on. That unit includes 50 “purchase strategists” and 100 technical experts. Moving from IKEA’s center to its periphery, we encounter 40 local Trading Offices employing 3,000 people who deal daily with suppliers. Therefore, IKEA’s multifaceted organization, with its many internal competences and external interfaces, is necessary for IKEA to pursue its network strategy and interact with the actors in its network. CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 113 Strategy in Industrial Networks: Experiences from IKEA Discussion: Structures and Dynamic Interactions in a Network Strategy What sustains IKEA’s network strategy? In other words, what are the key factors that enable IKEA to interact with its network in order to fulfill its efficiency and development goals? The framework introduced earlier contains both structural components and dynamic interactions. The idea is that before interacting with the network and using it dynamically, a network structure needs to emerge. This is clearly a simplification, because network structure and dynamics are tightly related. Indeed, a network structure can very well emerge more from ongoing interactions (inter-organizational routines or ad hoc projects)40 than from IKEA’s active choices to shape it. Still, as the purpose of this framework is to simplify matters, structural and dynamic factors are discussed separately. The Structural Components of a Network Strategy IKEA strives to shape the structure of its network by selecting suppliers, at least the 1,800 direct suppliers and logistic partners (see Figure 1). The structure and composition of this network are strategically important because they create both opportunities and restrictions for the actions that IKEA can undertake. Therefore, foresight is necessary over the goals to be reached, the resources needed to accomplish them, and the actors to be mobilized to access external resources. The actors and resources in IKEA’s network enable IKEA to achieve its main strategic goal: “providing inexpensive good-quality products to as many customers as possible.” Moreover, this network structure reflects more specific efficiency goals, such as low sourcing costs or smooth product flows, and development goals, such as new products or new technologies. Structural Component 1: Defining Relationship Contents Because of the importance of specific counterparts for achieving its goals IKEA needs to define the content of each relationship, in terms of exchange volumes, learning, trust, commitment, and duration. However, the content of one relationship cannot be defined in isolation from other relationships because it is related to the role played by that relationship in the overall network: for instance, compared to an interchangeable sub-supplier, a first-tier unique supplier often receives larger volumes, sustained by the high trust and commitment emerging from a long-term interaction. Not surprisingly, IKEA aims to strengthen the latter type of relationships. But among first-tier suppliers there are even more subtle differences based on the degree of IT integration with IKEA and on the operational responsibilities assigned to each supplier. To increasing supplier capabilities and commitment correspond increasing logistic responsibilities, according to a ladder model (see Figure 2). This increase in supplier responsibility entails an increase in IKEA’s dependence on selected suppliers. Another dimension to categorize relationship content is the initiative and leadership taken by a partner in development processes. In fact, partners such as Akzo-Nobel, who are formally second-tier suppliers, often display strong initiative and take a leading role because of their advanced technical competences 114 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA and their own network of contacts. This type of relationships entails important exchanges of technical knowledge with IKEA and is oriented towards the long term since many development processes are time-consuming. All the above forms of relationship content are issues that IKEA can rarely shape unilaterally. Moreover, IKEA’s ability to control and define a relationship’s content is even more limited for its indirect relationships, such as those between its direct suppliers and their sub-suppliers. Therefore, IKEA must agree to delegate, for instance, project leadership to a key partner that can select other actors and define the contents of their own relationships (as Swedwood and Akzo-Nobel do with their own partners). This delegation is extensive in development projects, where IKEA’s trusted key partners can partly affect the project goals and have ample freedom to mobilize other actors that have the required technical capabilities. IKEA’s delegation and a partner’s freedom in defining a relationship’s content are instead more restricted when it comes to inter-organizational routines (e.g., order management), which for efficiency’s sake need to be more controllable and uniform. However, even within IKEA’s direct relationships (e.g., with Swedwood), IKEA cannot unilaterally decide the relationship content. Content such as exchanged volumes, technical learning, and trust emerge instead from a twoparty game that requires the capabilities, engagement, and commitment of IKEA’s counterparts as well. In this game, IKEA is sometimes more powerful, especially in relation to smaller actors, but in other cases IKEA is so technically or volume dependent on certain counterparts that it must partly accept their efforts to shape the relationship content: for instance, exchanged volumes and technical investments are typically negotiated with key partners such as Swedwood. Structural Component 2: Forming the Network Structure Each relationship plays a well-defined role within a partly hierarchical structure. IKEA’s network includes, for instance, first-tier as well as second-tier suppliers, some of which play the role of “major” as opposed to “reserve” suppliers. Moreover, IKEA has direct relationships to certain actors (e.g., Swedwood) and indirect relationships to others (e.g., Sorbini). IKEA strives to shape this structure firstly by affecting the number of firms that are part of the network. For instance, between 2002 and 2007, IKEA reduced the number of direct suppliers from 2,400 to 1,300.41 Therefore, the remaining direct suppliers were given more responsibility. This implies not only larger volumes, but also that each direct supplier now handles more complex relationships with an increased number of sub-suppliers. Each relationship also has a specific function for the entire network because it connects other relationships: for instance, the relationship IKEA-Akzo assigns a leading role to Akzo in setting the technical agenda of its relationships with Sorbini and Bürkle (see Figure 3). Another network structure feature essential for a global player is the geographical spread of relationships. Suppliers are selected depending on the placerelated features of their resources (e.g., labor costs, raw materials, and proximity CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 115 Strategy in Industrial Networks: Experiences from IKEA to end markets) and on their role in IKEA’s network (e.g., project-leading partners need to be located near other involved units). The geographical structure of IKEA’s network is evolving towards a stronger emphasis on Chinese suppliers, who increased their share of IKEA’s purchases from 14% to 18% between 2003 and 2006. The macro-reasons behind this trend are not only easier communication and lower transportation and production costs, but also the technical advances made by Chinese suppliers, who now guarantee quality levels comparable with European ones. IKEA’s retail expansion in China further motivates selecting local suppliers, for both political and transport reasons. However, despite this geographic trend, suppliers from Sweden, Italy, and Poland still play a major role when it comes to sophisticated technical developments that require very specific competences, tight coordination, and co-location (see the Lack example). Although IKEA strives to shape the configuration of its network, its control over this structure is never complete: partners’ goals matter too. Furthermore, despite IKEA’s will, some actors take steps either to leave the network or to change their position within it (see the case of Becker-Acroma in Appendix A). IKEA’s control and overview of some parts of the network are also limited because some partners include in a project wholly new actors that IKEA had not considered. This happened, for instance, during the “printed veneer” project, whereby Akzo-Nobel involved a new equipment supplier, an Italian cylinder engraver, in IKEA’s network. In such cases, IKEA agrees to delegate to reliable partners not only the performance of key tasks, but also the selection into IKEA’s network of other relevant actors: this clearly affects the structuring of the network but is partly beyond IKEA’s control. Structural Component 3: Evaluating Goal Matching with the Network IKEA’s specific goals can be accomplished thanks to the resources of other firms and accessed through the direct and indirect relationships that shape a network structure (see Figures 1 and 3). Therefore, it is important to assess the matching of the goals and resources of the firms involved. A structure that enables matching includes both relationships that provide similar resources (e.g., IKEA’s parallel suppliers) and those that provide complementary resources (e.g., the relationships between IKEA’s suppliers and their own sub-suppliers). However, it is clear that IKEA’s goals and those of its partners do not always match each other. IKEA certainly seeks firms with which it can share goals at a general level: for instance, IKEA and Akzo-Nobel share the goal of developing coating technologies that improve furniture quality or costs. However, goals can sometimes be matched only after intense negotiations and discussions. Moreover, unexpected turns of events can change the initial goal congruence: this happened for example when IKEA decided not to launch the “printed on” Lack tables, which had been the main development goal of Swedwood and Akzo-Nobel. However, at a general level, Akzo-Nobel’s goal of developing new coating technologies could still be accomplished within its relationship to IKEA. In fact, IKEA is a perfect test customer that can subsidize 116 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA Akzo’s own developments: how many furniture retailers could afford to sacrifice thousands of real products just to perform technical tests? IKEA’s goals are more easily matched with those of the network in routine interactions, such as order management routines, which are applied daily without being questioned. However, goal convergence becomes more problematic in situations requiring development efforts and sacrifices from IKEA’s counterparts: for instance, rising conflicts over technical developments for IKEA’s Billy bookshelf induced the coating supplier Becker-Acroma to withdraw from an unwanted joint venture with IKEA (see Appendix A). Perfect goal congruence in the network cannot be achieved, simply because the network is not composed of firms that IKEA can unilaterally control. Despite IKEA’s size and power, these firms remain independent and hence are relatively free to set their own goals. More precisely, the goals of IKEA and all firms in the network are interdependent. This means that achieving one’s goal depends on the goals of other firms. Håkansson and Ford stress that managing the network is impossible or even undesirable.42 Instead, all firms need to manage in networks, which requires carefully taking into account the goals and resources of all the firms involved. Therefore, to enable “managing in the network,” a key component of a network strategy is assessing the matching between one’s own goals and those of the other firms involved. The Dynamic Interactions of a Network Strategy Next to evaluating and shaping the structure of the industrial network, it is necessary to understand what happens within this structure. Thus, the analytical focus shifts to the interaction processes that unfold in the network and that stand for its dynamics. These processes are particularly important because achieving strategic goals depends on how the interaction processes unfold, which now becomes more important than who performs them (i.e., the structural components). In strategic jargon, dynamic interactions are more concerned with implementation than are structural components, but they are essential to achieving the specific efficiency and development goals associated with a given network structure. While forming the network structure can rely on simply assessing the matching between internal and external resources, implementing a network strategy with specific goals requires combining dynamically and more profoundly the resources in the network. These concrete resource combinations are created through continuous interaction processes. For instance, through the order management routines, IKEA achieves efficiency when all firms involved combine daily such resources as 12,000 products, countless components, transport means, and their specific competences. Resource combinations are particularly dynamic when the goal is to develop new technologies: during the “printed veneer” project, coating-related resources were combined and recombined in complex ways, as witnessed by the many tests required to find out how new resources could work together. CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 117 Strategy in Industrial Networks: Experiences from IKEA Inter-organizational routines and projects drive a network strategy because they are the concrete mechanisms through which relationships are practically mobilized and they provide the context in which dynamic resource combinations occur. However, these two types of interaction processes differ in their functions and applicability to efficiency goals, for which routines are more appropriate, as opposed to development goals, for which projects are a better mechanism. Dynamic Interactions 1: Interacting via Inter-Organizational Routines Compared to development projects, inter-organizational routines are more structured and rigid mechanisms because they clearly specify in advance the nature and timing of the activities performed by IKEA and its partners. For these reasons, inter-organizational routines are adequate for daily interactions that aim to maintain efficiency. Examples of key efficiency goals for IKEA include reduced lead-times and inventory costs as well as more precise deliveries. To achieve such goals, order management routines, for instance, clearly specify the time frames, each actor’s roles, the interaction patterns, and the resources involved. The continuous performance of inter-organizational routines also brings about adaptations in the firms’ activities that can be better linked for mutual efficiency gains, as stressed by Håkansson and Snehota.43 Moreover, according to Zollo, Reuer, and Singh, inter-organizational routines improve the performance of cooperative agreements.44 Still, compared to the open-ended nature and ample delegation of joint projects, IKEA strives to control more unilaterally the performance of critical routines such as order management, for the sake of certainty and homogeneity across its network. Therefore, these inter-organizational routines need to closely follow the script that IKEA requires from its partners. Dynamic Interactions 2: Interacting via Joint Projects Joint projects are ad hoc and more flexible mechanisms than routines, and are therefore employed for interaction processes that aim to foster product and technology development.45 For instance, the “printed veneer” project had rather broad goals (i.e., tackling the issue of costly veneers), timeframes, roles, and interaction patterns, and many unplanned resources could be involved as the project unfolded. In comparison to routines, projects entail less control and more uncertainty for IKEA. For instance, the “printed veneer” project was highly uncertain because it was rather open-ended and technically challenging and had an open timeframe. Moreover, IKEA was not able to control the selection of new participants in this project, as the technical leadership was assigned to Akzo. Nevertheless, no matter how strongly IKEA can control a project, interorganizational projects are important drivers of development for at least three reasons: they organize IKEA’s interactions with its network by allocating tasks and responsibilities, they focus attention and efforts on a specific development problem, and they select and mobilize key actors who can contribute relevant knowledge to tackle the problem at hand. Similar advantages of projects as tools 118 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA to foster innovation have been recognized (although in an intra-organizational context) by Bowen, Clark, Holloway, and Wheelwright.46 Moreover, as stressed by Brady and Davies,47 projects facilitate “explorative” learning, that is, they enable learning by exploring new areas of knowledge. Such exploration is particularly important when IKEA does not know what technology needs to be developed or who can develop it, as in the case of “printed veneer.” Then, the flexibility of projects as coordination mechanisms comes in handy, together with IKEA’s delegation to selected actors, who are in turn free to engage their own trusted partners. Furthermore, if the new actors remain permanently engaged, projects assume an even broader renewal potential by affecting the structure and composition of IKEA’s network. Granted the importance of the external network for IKEA, a natural question is: What does IKEA need to have itself in order to interact successfully with this network? IKEA’s competence, organizational structure, and culture are important prerequisites for IKEA to be able to initiate and take part in the interaction processes that drive its network strategy. Those internal features strongly affect how the focal firm interacts with specific partners, via inter-organizational routines and joint projects,48 and are fundamental for any strategic center to successfully interact with a web of partners.49 Firstly, IKEA possesses strong competences in all areas necessary to interact with and support suppliers: IKEA of Sweden employs about 100 experts in important areas for its product and technology development, such as wooden materials, coatings, and surface treatments; while to support interactions with manufacturers and carriers concerning distribution routines, IKEA of Sweden employs about 100 logistics and order management experts. These technical and logistic competences are also reproduced on a local level within IKEA’s Trading Offices. Secondly, IKEA has created both central and local organizational interfaces to interact with suppliers. The central business unit, IKEA of Sweden, both negotiates with major suppliers the worldwide prices and discusses long-term investments and capacity plans. IKEA of Sweden also intervenes during supplier selections and extensive development projects. Alongside these central interorganizational interfaces, IKEA also interacts locally with single suppliers through its 40 Trading Offices. These business units are in charge, first and foremost, of daily issues such as ordering and logistic coordination; but they also intervene in yearly capacity planning and supplier selection meetings, where they represent their own local suppliers against other Trading Offices. Thirdly, IKEA’s culture may be inspired by cost-containment, but there is a strongly rooted understanding that this goal requires mutual long-term commitments with key external partners. These values inspire IKEA’s criteria for supplier selection (which stress a supplier’s readiness to make long-term investments for and with IKEA) and management systems (which reward Trading Offices based on the volumes that they, together with their local suppliers, supply to IKEA worldwide). Such mechanisms strengthen the specific Trading Office-supplier relationship and facilitate the emergence of mutual trust. Thus, IKEA can accept the neces- CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 119 Strategy in Industrial Networks: Experiences from IKEA sity of being dependent on certain highly trusted partners without the need to unilaterally control the relationship. However, despite IKEA’s positive experiences, its competences and organizational structure often need to change to fit specific partners and interaction processes that unfold in the network. Changes in IKEA’s competences may be necessary to exploit new opportunities and are often driven by joint projects: for instance, IKEA learned new coating technologies and “VMI” by interacting with its suppliers and logistic partners. A specific joint project may even lead IKEA to create special business units (see the joint venture GIAB presented in Appendix A). On a broader scale, IKEA currently deals with three major organizational changes stimulated by developments in the network: opening new Trading Offices in countries offering interesting sourcing opportunities; increasing the responsibilities and competences of Trading Offices in Asia, as a reaction to the increased volumes and know-how of Asian suppliers; and creating direct interfaces between retail stores and selected suppliers, in order to improve product development and deliveries during sales promotions. Conclusions and Implications from the IKEA Case Industrial networks and business relationships play key roles for the strategy of IKEA and of most firms. Therefore, firms need a “network strategy,” that is, they need to consider and use the external network in order to accomplish their own goals. The framework presented in this article helps to systematize the factors that can improve interaction with the external network. The structural components and the dynamic interactions were elaborated on the basis of IKEA’s network strategy; the key implications of IKEA’s experiences of network interactions can be summarized as follows: ▪ In order for a firm to implement a network strategy and achieve its own goals, the focal firm’s resources must be combined with those of external actors. This combination is made concrete through two types of interaction processes: inter-organizational routines—well suited for achieving efficiency goals—and joint projects, aptly addressing development goals. ▪ These interaction processes are facilitated if the goals and resources of the various parties match each other. However, perfect goal congruence never exists in a network of independent firms. Therefore, evaluating the goal and resource matching with specific counterparts can help in two major ways: in choosing from the beginning partners with more attuned resources and goals (e.g., those willing to make long-term commitments); and in supporting the negotiations necessary to increase the goal congruence with specific partners. ▪ Even if a firm can improve its “network matching” by forming the structure of the network (e.g., by selecting suppliers), no absolute control can be established over the network. Some counterparts may not accept the relationship content expected by the focal firm, or may even choose to interrupt their interactions and leave the network. Therefore, business 120 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA relationships with key partners need to be carefully handled to establish strong outposts in the network. In fact, the limits to controlling the network structure and processes suggest the need to delegate responsibilities to trusted and competent external actors who are capable, in turn, of engaging other relevant actors. This is what IKEA does, and it is especially important in technical development projects that involve very widespread competences. ▪ The external network cannot compensate for the gaping weaknesses of unprepared firms: the strategic center cannot be “hollow.” In fact, forming the network by attracting counterparts and continuously interacting with them requires that a firm is capable and prepared to “meet the network” in three main ways: by possessing extensive and specialized competences (see IKEA’s considerable logistic and technical competences); by creating appropriate inter-organizational interfaces (see IKEA’s many specialized purchasing units and its product developers, who travel 200 days a year to meet suppliers); and by promoting a network-oriented culture that favors a long-term approach and the creation of mutual trust instead of the abuse of power over partners. ▪ While being prepared to “meet the network” also means being flexible enough to change internal competences and inter-organizational interfaces to better interact with a changing network, a network-oriented culture is instead more of a stable pillar. In fact, IKEA’s entire network strategy strongly relies on mutual trust and commitment to selected partners as substitutes for absolute control: its is only if you trust a committed partner that you can accept dependence on it and delegate essential tasks such as technical developments. However, trust and commitment do not appear overnight in a business relationship, but require a long-term approach. This is why IKEA takes so seriously its supplier development programs to improve selected partners’ IT and logistics capabilities (see Figure 2) or its joint technical development projects. These initiatives take time, but they eventually pay off when these suppliers can be more trusted for IKEA’s daily replenishments or for technology issues. APPENDIX A From Saving the “Billy” Bookshelf to Conflicts with Suppliers The “Billy” bookshelf is one of IKEA’s best sellers; it sells over one million units yearly. In the 1980s, Billy was one of IKEA’s most representative products, strongly associated with its design style and with its image of a family-friendly company. However, this situation came under threat in 1991, when traces of formaldehyde were found in Billy packs in Germany. In IKEA’s largest market, the media started accusing IKEA of “poisoning” customers: a commercial catastrophe and a complete loss of reputation were near, and IKEA had to solve the problem rapidly in order to restore its goodwill. IKEA of Sweden began a close CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 121 Strategy in Industrial Networks: Experiences from IKEA scrutiny of the whole production process at Sydpoolen, a group of Swedish suppliers that manufactured Billy. The coating process soon became the key suspect, since hazardous chemicals were used in this production phase, and there was a risk that these chemicals might remain on the surface of the furniture. In a state of emergency, IKEA of Sweden mobilized Becker-Acroma, one of its major coating suppliers. In consultation with Sydpoolen’s technicians, they were able to relate the formaldehyde emissions to two causes: the use in Sydpoolen’s factories of acid-curing coatings known to emit this gas; and too short a time between curing and packaging, which did not allow all the formaldehyde to dissipate before packing took place. Therefore, the first action taken was prohibiting the use of acid-curing coatings at all IKEA’s suppliers. Meanwhile, Becker and other coating producers started supplying an older technology known as water-borne lacquers. IKEA, however, saw this solution as only temporary, and started searching for a robust solution. Becker suggested the use of UV-curing, in which ultra-violet lamps are used to attach coatings to wood panels. After a few months, IKEA also founded GIAB, a new firm with the specific purpose of making this UV technology more economically viable and introducing it to all IKEA’s suppliers. At the same time, IKEA made it clear to all the firms involved with this technology that they were required to take shares in GIAB, which was then transformed into a joint venture. Among these actors were Becker-Acroma, Sydpoolen, and the sub-supplier of wood panels. GIAB was equipped with a UV-based coating line that functioned as a full-scale testing facility around which the above actors gathered to perform tests. The goal was to find out how coatings needed to be modified and which parameters should be reproduced in the coating lines of other IKEA suppliers. These resources are shown in Figure A1. IKEA’s goal with the joint venture GIAB was then extended to making it a powerhouse for the development of furniture coating technologies in general. However, even though cooperation was achieved on the factory floor, the project was ridden with conflicts. Becker-Acroma felt that the coating suppliers had been used by IKEA as scapegoats for the Billy “scandal,” and that they were now obliged to do most of the work of finding a solution. Becker-Acroma also saw the establishment of GIAB as an accusation that these suppliers were incapable of developing new solutions by themselves. Despite these hard feelings, many tests were performed, which eventually led to finding the right combination of UV coatings, particle boards, and coating lines. During the 1990s, this technology was rolled out across all IKEA suppliers, which today use UV curing almost exclusively. However, the forced cooperation eventually became unacceptable, especially to larger actors such as Becker-Acroma, who more or less stopped contributing to GIAB’s development. Therefore, at the end of the 1990s, despite IKEA’s plans to turn GIAB into a consultant with its own customers outside the IKEA universe, GIAB lost momentum, firstly as it had fulfilled its task, and secondly as it had never been accepted by coating producers. 122 UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA FIGURE A1. The Network of Resources Combined during Billy’s Coating Project IKEA Wood Panel Producer Wood Panel Coating Lines GIAB Sydpoolen Test Facility Coatings “Billy” Becker-Acroma Notes 1. Next to 70 in-depth interviews, the empirical material was collected via a dozen visits and site observations made at IKEA and its suppliers’ facilities in Sweden, Poland, and Italy. These sources were completed by first-hand written sources such as documents, catalogues, brochures, and company presentations, and by secondary sources such as newspaper clips and other publications related to IKEA. 2. For examples in the software sector, see B. Iyer, C.H. Lee, and N. Venkatraman, “Managing in a ‘Small World Ecosystem’: Lessons from the Software Sector,” California Management Review, 48/3 (Spring 2006): 28-47. For examples in the biotech sector, see W. W. Powell, K.W. Koput, and L. Smith-Doerr, “Interorganizational Collaboration and the Locus of Innovation: Networks of Learning in Biotechnology,” Administrative Science Quarterly, 41/1 (March 1996): 116-145; W.W. Powell, “Learning From Collaboration: Knowledge and Networks in the Biotechnology and Pharmaceutical Industries,” California Management Review, 40/3 (Spring 1998): 228-240. 3. See the Sassuolo area in Italy as featured in M. Russo, “Technical Change and the Industrial District: The Role of Interfirm Relations in the Growth and Transformation of Ceramic Tile Production in Italy,” Research Policy, 14/6 (December 1985): 329-343; M. Russo, “Complementary Innovations and Generative Relationships: An Ethnographic Study,” Economics of Innovation & New Technology, 9/6 (December 2000): pp. 517-557. 4. See the study on the garment industry in New York City by B. Uzzi, “Social Structure and Competition in Interfirm Networks: The Paradox of Embeddedness,” Administrative Science Quarterly, 42/1 (March 1997): 35-67. 5. See M.H. Lazerson and G. Lorenzoni, “The Firms that Feed Industrial Districts: A Return to the Italian Source,” Industrial and Corporate Change, 8/2 (1999): 235-265. 6. See B.R. Koka and J.E. Prescott, “Strategic Alliances as Social Capital: A Multidimensional View,” Strategic Management Journal, 23/9 (September 2002): 795-806; E.H.M. Moors and P.J. CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 123 Strategy in Industrial Networks: Experiences from IKEA 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 124 Vergragt, “Technology Choices for Sustainable Industrial Production: Transitions in Metal Making,” International Journal of Innovation Management, 6/3 (September 2002): 277-299. T. Wedin, Networks and Demand: The Use of Electricity in an Industrial Process (Uppsala, Sweden: Department of Business Studies, Uppsala University, 2001). See I. Stuart, P. Deckert, D. McCutcheon, and R. Kunst, “A Leveraged Learning Network,” Sloan Management Review, 39/4 (Summer 1998): 81-93; C. Carr and J. Ng “Total Cost Control: Nissan and Its U.K. Supplier Partnerships,” Management Accounting Research, 6/4 (December 1995): 347-365. The list is presented on page 148 of G. Lorenzoni and C. Baden-Fuller, “Creating a Strategic Center to Manage a Web of Partners,” California Management Review, 37/3 (Spring 1995): 146-163. See W.W. Powell, “Hybrid Organizational Arrangements: New Form or Transitional Development?” California Management Review, 30/1 (Fall 1987): 67-87. Networks have probably always been there, since the early days of the modern corporations, even if periodic increases in vertical integration tend to hide inter-firm networks. Even the Fordistic model emerged in the early 1900s from a highly networked structure in the car industry. See pages 365-368 in R.N. Langlois and P.L. Robertson, “Explaining Vertical Integration: Lessons from the American Automobile Industry,” Journal of Economic History, 49/2 (June 1989): 361-75. These types of adversarial postures were for instance typical in the car industry until the early 1980s, as discussed by L.-E. Gadde and H. Håkansson, Professional Purchasing (London: Routledge, 1993). Dominating paradigms within strategic management have been for decades the microeconomics-inspired Industrial Organization [see J.S. Bain, “The Theory of Monopolistic Competition After Thirty Years: The Impact on Industrial Organization,” American Economic Review, 54/3 (May 1964): 28-32; M.E. Porter, Competitive Strategy: Techniques for Analyzing Industries and Competitors (New York, NY: Free Press, 1980)] and Transaction Cost Economics [see O.E. Williamson, “The Economics of Organizing: The Transaction Costs Approach,” American Journal of Sociology, 87/3 (November 1981): 548-577; “Strategizing, Economizing, and Economic Organization,” Strategic Management Journal, 12/8 (Winter 1991): 75-94]. Whereas Industrial Organization could not consider networks because it used as key unit of analysis whole sectors, Transaction Costs Economics views inter-firm relationships and networks as exceptions in economic organizing. G.B. Richardson, “The Organization of Industry,” Economic Journal, 82/327 (September 1972): 883-896. M.S. Granovetter, “Economic Action and Social Structure: The Problem of Embeddedness,” American Journal of Sociology, 91/3 (November 1985): 481-510. W.W. Powell, “Neither Market Nor Hierarchy: Network Forms of Organization,” in B.M. Staw and L.L. Cummings, eds., Research in Organizational Behavior, Vol. 12 (Greenwich CT: JAI Press, 1990), pp. 295-336. R. Swedberg, “Markets as Social Structures,” in N.J. Smelser and R. Swedberg, eds., The Handbook of Economic Sociology (Princeton, NJ: Princeton University Press, 1994), pp. 255282. Even scholars studying strategic alliances are dissatisfied with the research bias towards applying atomistic views to interactive phenomena such as alliances. For instance, Ranjay Gulati called for a paradigm shift, from an atomistic to a social network-embedded view of alliances. See page 295 in R. Gulati, “Alliances and Networks,” Strategic Management Journal, 19/4 (April 1998): 293-317. This view is presented for instance by H. Håkansson, “Organization Networks,” in A. Sorge and M. Warner, eds., The IEBM Handbook of Organizational Behaviour (London: Thomson Business Press, 1997), pp. 232-239; M.J. Piore, “Fragments of a Cognitive Theory of Technological Change and Organizational Structure,” in N. Nohria and R.G. Eccles, eds., Networks and Organizations: Structure, Form and Action (Boston, MA: Harvard Business School Press, 1992), pp. 430-444. Markets and hierarchies, the norms in many established theories (e.g., marketing, strategy), would then become just extreme cases whereby the informal network interactions are constrained either inside a strict hierarchy (based on command and bureaucratization) or by a perfect market (composed of autonomous firms that coordinate solely via price signals). See H. Håkansson, “Product Development in Networks,” in H. Håkansson, ed., Industrial Technological Development—A Network Approach (London: Croom Helm, 1987), pp. 84-115. UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU Strategy in Industrial Networks: Experiences from IKEA 22. See Wedin, op. cit. 23. See E. Baraldi, When Information Technology Faces Resource Interaction: Using IT Tools to Handle Products at IKEA and Edsbyn (Uppsala, Sweden: Department of Business Studies, Uppsala University, 2003). 24. A comprehensive literature overview over the IMP tradition is presented on pages 25-30 of H. Håkansson and A. Waluzsewski, Managing Technological Development: IKEA, the Environment and Technology (London: Routledge, 2002). 25. These studies included both a large-scale questionnaire studying hundreds of business relationships in Europe in the late 1970s and numerous extensive, deep case studies. The latter research approach still characterizes current IMP research: since the 1970s, hundreds of case studies have traced the industrial network around a focal firm or a technical solution by means of snowballing data collection techniques reaching up to 100 interviews. 26. See G.C. Homans, Social Behavior: Its Elementary Forms (New York, NY: Harcourt, Brace & World, 1961); S. Macaulay, “Non-Contractual Relations in Business: A Preliminary Study,” American Sociological Review, 28/1 (February 1963): 55-67; P.M. Blau, “The Hierarchy of Authority in Organizations,” American Journal of Sociology, 73/4 (January 1968): 453-467. 27. See, for instance, the model on page 24 of H. Håkansson, ed., International Marketing and Purchasing of Industrial Goods: An Interactive Approach (Chichester: Wiley, 1982). 28. An example of these network-level models is the so-called “ARA” model, which decomposes the substance of industrial networks into three layers: inter-firm Activity patterns, Resource constellations, and webs of Actors. This Activity-Resource-Actor model is elaborated in H. Håkansson and I. Snehota, eds., Developing Relationships in Business Networks (London: Routledge, 1995). 29. See J.C. Anderson, H. Håkansson and J. Johanson, “Dyadic Business Relationships Within a Business Network Context,” Journal of Marketing, 58/4 (October 1994): 1-15; L. Hallén, J. Johanson, and N. Seyed-Mohamed, “Interfirm Adaptation in Business Relationships,” Journal of Marketing, 55/2 (April 1991): 29-37. 30. See U. Andersson and M. Forsgren, “Subsidiary Embeddedness and Control in the Multinational Corporation,” International Business Review, 5/5 (October 1996): 487-508; and U. Andersson, M. Forsgren and U. Holm, “The Strategic Impact of External Networks: Subsidiary Performance and Competence Development in the Multinational Corporation,” Strategic Management Journal, 23/11 (November 2002): 979-996. 31. For a Markets-as-Networks view of business strategy, see H. Håkansson and I. Snehota, “No Business is an Island: The Network Concept of Business Strategy,” Scandinavian Journal of Management, 5/3 (1989): 187-200. 32. The concept of “strategic center” is used by Lorenzoni and Baden-Fuller, op. cit. 33. There is, in fact, also a “dark side” of networks, stressed for instance by H. Håkansson and I. Snehota, “The Burden of Relationships or Who’s Next?” in D. Ford, ed., Understanding Business Markets (London: Thompson Learning, 2002), pp. 88-94. Networks do not only produce positive effects for development and efficiency, but they are also ridden with conservative forces that embed (in the sense of “constraining”) the firm. Too close business relationships can be harmful for novelty, a problem defined as “over-embeddness” by Uzzi [op. cit., pp. 60-63]. However, the dark side of networks derives not only from social aspects: networks can in fact generate technical lock-ins and economic overdependence for the involved firms. 34. In fact, business relationships require time to be established, but then display a strong continuity and can stretch over decades (as is the case for several of IKEA’s relationships). This continuity includes institutionalization and dependencies that make relationships hard to change or terminate. These combined effects create stability in a network, where the involved actors, their goals, and their resources change only slowly. For the structural characteristics of business relationships and networks, see H. Håkansson and I. Snehota, eds., Developing Relationships in Business Networks (London: Routledge, 1995). 35. For a description of Wal-Mart’s supplier relationships, see M. Petrovic and G.G. Hamilton, “Making Global Markets: Wal-Mart and Its Suppliers,” in N. Lichtenstein, ed., Wal-Mart: The Face of Twenty-First-Century Capitalism (New York, NY: The New Press, 2006), pp. 122-138. 36. IKEA’s approach can be contrasted with Charles Fishman’s rendering of Wal-Mart: “WalMart has the power to squeeze profit-killing concessions from suppliers...Wal-Mart price pressure can leave so little profit that there is little left for innovation.” The quote is found in C. Fishman, The Wal-Mart Effect (New York, NY: Penguin, 2006), p. 89. 37. For the basic features of Keiretsu, see K. Miyashita and D. Russell, Keiretsu: Inside the Hidden Japanese Conglomerates (New York, NY: McGraw-Hill, 1994); H. Kim, R.E. Hoskisson and CALIFORNIA MANAGEMENT REVIEW VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU 125 Strategy in Industrial Networks: Experiences from IKEA 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 126 W.P. Wan, “Power Dependence, Diversification Strategy, and Performance in Keiretsu Member Firms,” Strategic Management Journal, 25/7 (July 2004): 613-636. See Fishman, op. cit.; C. Fishman, “The Wal-Mart Effect and a Decent Society: Who Knew Shopping Was So Important?” Academy of Management Perspectives, 20/3 (August 2006): 6-25, at pp. 13-14. For a comprehensive analysis of how IKEA utilizes geographical factors across several places, see E. Baraldi, “The Places of IKEA: Using Space in Handling Resource Networks,” in E. Baraldi, H. Fors, and A. Houltz, eds., Taking Place: The Spatial Contexts of Science, Technology, and Business (Sagamore Beach, MA: Science History Publications, 2006), pp. 297-320. Development projects, regarded here as dynamic interactions, entail also strong structuring elements: even in informal projects, a specific organization—”a network in the network”— is typically built. This can alter the content of existing relationships between IKEA and its partners, as it partly did in the Billy episode among IKEA and Becker-Acroma (see Appendix A). Moreover, IKEA’s technical projects are often an occasion for new actors to be included in the structure of IKEA’s network: the “printed veneer” project, for instance, involved for the first time an Italian firm that is now a stable supplier of engraved cylinders. Meeting with Anders Brorström, Deputy Procurement Director, IKEA Russia, Moscow, February 28, 2007. See H. Håkansson and D. Ford, “How Should Companies Interact in Business Networks?” Journal of Business Research, 55/2 (February 2002): 133-139. On page 138, the authors stress that achieving total control over a network, however unlikely it is, is undesirable because it would transfer all burden and source of innovation and wisdom to the controlling company itself. On the concept of “activity links,” one of the key dimensions in the IMP network “ARAmodel,” see H. Håkansson and I. Snehota, eds., Developing Relationships in Business Networks (London: Routledge, 1995), pp. 28-30. See M. Zollo, J.J. Reuer, and H. Singh, “Interorganizational Routines and Performance in Strategic Alliances,” Organization Science, 13/6 (November/December 2002): 701-713. These advantages of both intra- and inter-organizational projects as coordination mechanisms are recognized, for instance, by J. Sydow, L. Lindkvist, and R. DeFilippi, “ProjectBased Organizations, Embeddedness, and Repositories of Knowledge: Editorial,” Organization Studies, 25/9 (November 2004): 1475-1489. H.K. Bowen, K.B. Clark, C.A. Holloway, and S.C. Wheelwright, “Development Projects: The Engine of Renewal,” Harvard Business Review, 72/5 (September/October 1994): 110-120. See T. Brady and A. Davies, “Building Project Capabilities: From Explorative to Exploitative Learning,” Organization Studies, 25/9 (November 2004): 1601-1621, at 1605-1607. A routine such as OPDC strongly depends on IKEA’s competences and organization and is impossible to perform without adequate external interfaces. The effect of IKEA’s internal structure is present, although less evident, on development projects, whose success certainly depends on IKEA’s competence and organizational structure, but where much responsibility and control is typically delegated to actors farther away from IKEA. See Lorenzoni and Baden-Fuller, op. cit. UNIVERSITY OF CALIFORNIA, BERKELEY VOL. 50, NO. 4 SUMMER 2008 CMR.BERKELEY.EDU MANAGEMENT SCIENCE informs Vol. 56, No. 3, March 2010, pp. 468–484 issn 0025-1909 eissn 1526-5501 10 5603 0468 ® doi 10.1287/mnsc.1090.1117 © 2010 INFORMS The Impact of Misalignment of Organizational Structure and Product Architecture on Quality in Complex Product Development Bilal Gokpinar Department of Management Science and Innovation, University College London, London WC1E 6BT, United Kingdom, [email protected] Wallace J. Hopp Stephen M. Ross School of Business, University of Michigan, Ann Arbor, Michigan 48109, [email protected] Seyed M. R. Iravani Department of Industrial Engineering and Management Sciences, Northwestern University, Evanston, Illinois 60208, [email protected] P roduct architecture and organizational communication play significant roles in complex product development efforts. By using networks to characterize both product structure and communication patterns, we examine the impact of mismatches between these on new product development (NPD) performance. Specifically, we study the vehicle development process of a major auto company and use vehicle quality (warranty repairs) as our NPD performance metric. Our empirical results indicate that centrality in a product architecture network is related to quality according to an inverted-U relationship, which suggests that vehicle subsystems of intermediate complexity exhibit abnormally high levels of quality problems. To identify specific subsystems in danger of excessive quality problems, we characterize mismatches between product architecture and organizational structure by defining a new metric, called coordination deficit, and show that it is positively associated with quality problems. These results deepen our understanding of the impact of organizational structure and product architecture on the NPD process and provide tools with which managers can diagnose and improve their NPD systems. Key words: new product development; product architecture; organizational structure; complex networks History: Received June 23, 2008; accepted August 30, 2009, by Christoph Loch, R&D and product development. Published online in Articles in Advance January 12, 2010. 1. Introduction and Literature Review that make up the product, and (2) how to ensure that people communicate/collaborate effectively in the performance of design tasks. As evidence that these problems are universal and difficult, a recent joint study by BusinessWeek and the Boston Consulting Group, reported that 1,000 senior managers around the globe cited a lack of coordination as the secondbiggest barrier to innovation (McGregor 2006). From an operations management standpoint, we can view the new product development (NPD) process as a network of engineers designing a network of parts. Consequently, in this paper, we study the problem of coordinating parts and people in an NPD process by means of network analysis. As such, this paper is part of a growing literature that makes use of networks to represent both product architecture (Krishnan and Ulrich 2001, Henderson and Clark 1990, Ulrich 1995) and organizational structure (Clark and Fujimoto 1991, Brown and Eisenhardt 1995). In the work closest to our own, Sosa et al. (2004) adopted Product innovation is central to business creation and growth. Firms that are able to bring a steady stream of timely and well-executed products to market are likely to enjoy long-term financial success. Designing products and bringing them to market, however, is not a straightforward process. Product development efforts usually involve many design iterations. The ability of the organization to manage these inevitable design changes has a major impact on product quality and firm competitiveness. The development process is particularly challenging for complex products such as automobiles or airplanes, which involve thousands of engineers spending years designing, testing, and integrating hundreds of thousands of parts. Consequently, a key challenge in these product development processes is matching the organization to the product being developed. This involves two fundamental problems: (1) how to assign people to the parts and subsystems 468 Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture Management Science 56(3), pp. 468–484, © 2010 INFORMS a combined perspective in a study of the alignment of design interfaces and communication patterns. In a subsequent paper, they identified factors that make some teams better than others at aligning their crossteam interactions with design interfaces (Sosa et al. 2007). Although the insights from these studies are interesting and potentially useful in improving NPD processes, they are premised on a basic assumption, namely that misalignment of the design organization and the product architecture is detrimental to performance. But, because none of these studies actually measured performance, they could not corroborate this assumption. In this paper, we build on this stream of research by (a) defining a new metric, called coordination deficit, which quantifies mismatches between product architecture and organizational structure, and (b) empirically investigating the effect of coordination deficit on product quality. In a broader sense, our work builds upon and integrates two streams of research: (i) operations of complex product development and (ii) social network analysis of organizational performance. Although these areas are very broad and have been studied from a variety of perspectives, they have been studied together under two major research headings: knowledge networks (see Nonaka and Takeuchi 1995, Contractor and Monge 2002) and modularity (see Ulrich 1995, Baldwin and Clark 2000). Researchers have investigated various aspects of knowledge networks in the context of product development and have provided critical insights into why some business units are able to make effective use of knowledge from other parts of the company, while other units find knowledge to be a barrier to innovation (Hansen 2002, Carlile 2002). In this paper, we construct a very specific knowledge network that characterizes collaboration and communication between design engineers and identify structural features of this network that are correlated with quality problems in the final product. Modularity refers to methods for reducing the number of interactions and interfaces among parts and components in product design (Ulrich 1995, Baldwin and Clark 2000). Organizational implications of modularity, as well as the organizational factors that support the use of modularity, have been studied by several researchers (see Sanchez and Mahoney 1996, Schilling 2002, Ethiraj and Levinthal 2004, Fleming and Sorenson 2004). Unlike other network studies of modularity, which represent interfaces as either present or not present, we make use of engineering data to characterize the strength of interfaces between components. This gives us a more detailed representation of the product architecture, which we compare 469 to the organizational structure to quantitatively measure the degree of misalignment. This paper also contributes to the literature on the use of social network tools in empirical studies of organizations (see, e.g., Wasserman and Faust 1994). A distinctive feature of our study is that we make use of archival data, rather than surveys, to construct a social network. Because such data is readily available in NPD environments, this approach may ultimately make network analysis more practical as a management tool. Finally, from a practical perspective, our work can help managers to systematically identify and quantify potential problem areas that can be addressed to improve the quality of the resulting products. Our metric of organizational misalignment (i.e., coordination deficit) can be computed using standard data from an engineering change order system. As such, it provides a way to highlight opportunities for improving coordination among design engineers without collecting additional data. This should be particularly valuable in environments where evolution of product architectures changes coordination needs over time and makes static organizational policies ineffective. The remainder of this paper is organized as follows. In §2, we provide the theoretical background and frame our hypotheses. In §3, we present a detailed description of the data and the system in which we test the hypotheses. In §4, we describe the model development, and in §5, we present the analysis and results. We discuss our results in §6 and conclude in §7. 2. Theory and Hypotheses Ulrich (1995, p. 420) defined product architecture as “(i) the arrangement of functional elements, (ii) the mapping from functional elements to physical components, and (iii) the specification of the interfaces among interacting physical components.” All three of these dimensions may influence ultimate product performance at either the local (component) level (Ulrich 1995, Baldwin and Clark 2000, Mihm et al. 2003) or the global (product) level (Clark and Fujimoto 1990). An intermediate level between the component and product levels is the subsystem level, which is widely used by firms to describe product architectures for management purposes. From a network perspective, product architecture can be characterized by representing subsystems as nodes and interfaces between subsystems as links. Network metrics can then be used to describe the nature and position of product subsystems. For example, a subsystem with many (physical and functional) interfaces will have high centrality in the product architecture network. Given this interpretation, the centrality of a subsystem can serve as a proxy for complexity, because 470 Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture more interfaces imply more design issues. So, if management were to devote equal resources and attention to all subsystems, we would expect highly central subsystems to exhibit worse performance (e.g., more quality problems). But management does not usually do this. Previous research on product development has shown that architectural/technical interdependence is associated with organizational communication (Henderson and Clark 1990, Brown and Eisenhardt 1995, Adler et al. 1995). Highly central subsystems, which are heavily connected to other subsystems, logically receive intense attention from the organization, which offsets the potential quality problems resulting from their complexity. If management were to perfectly correlate resources and attention to the complexity of each subsystem, we would not expect to see any correlation at all between centrality and performance (e.g., quality). But we do not think this is realistic either. Complexity is not directly observable. Therefore, mismatches between organizational attention and subsystem interconnectivity, of the type observed by Sosa et al. (2004), are likely to occur. We conjecture that they are most likely to occur for subsystems of intermediate centrality. The reason is that highly central subsystems are obviously highly complex, and hence receive substantial organizational attention. Indeed, they may receive even more attention than they need because they present such manifest design challenges. At the other end of the scale, low centrality subsystems, which have few interfaces, require relatively little coordination effort and so are unlikely to be underattended. Even the minimal amount of organizational coordination built into standard design practices is likely to be enough for these subsystems. But intermediate centrality subsystems are neither complex enough to be obvious nor simple enough to be easy. These are the subsystems where a delicate matching of resources and attention to the design complexity is most difficult. Therefore, this is where we expect to find the most mismatches, as we conjecture in the following hypothesis: Hypothesis 1. The centrality of a product subsystem in the product architecture has an inverted-U association with the quality problems observed in that subsystem. The earlier discussion provides a very general sense of where a lack of organizational coordination might lead to excessive quality problems. But because centrality only characterizes subsystems in a coarse manner, it would not provide any explicit managerial guidance on which subsystems are most prone to quality problems. Henderson and Clark (1990) established a relationship between product architecture and design organization, and pointed out the importance of matching team interfaces to technical Management Science 56(3), pp. 468–484, © 2010 INFORMS interfaces. Sosa et al. (2004) observed that product development teams tend to ignore certain types of technical interfaces. In a more recent study, Sosa et al. (2007) presented anecdotal evidence from industry where the shortage of organizational attention to technical interfaces resulted in poor performance. Based on these findings and the intuition of NPD managers in our client firm, we conjecture the following hypothesis: Hypothesis 2. Mismatches between product architecture and organizational coordination in subsystems are positively associated with the quality problems observed in these subsystems. We note, however, that neither Henderson and Clark (1990) nor Sosa et al. (2004) actually measured NPD process performance to test the above hypothesis. To do this, we will first establish a quantitative measure of the degree of mismatch between the organization and the product and then correlate this metric with empirically observed performance (i.e., warranty claims). 3. Overview of the Vehicle Development Process Our empirical analyses are based on a detailed study of the new vehicle development process of a large U.S. auto manufacturer. Because it involves many interdependent tasks over an extended period, automotive design is a prototypical example of complex product development. To create a useful model, one of the authors spent two summers (about six months) on site for data collection and analysis. This allowed us to gain a good understanding of the product development process through observation of common practices and obstacles. We also collected an extensive data set from the engineering change order (ECO) system, which is used by the firm to manage and document the design process. 3.1. Vehicle Development Process Our main unit of reference regarding the vehicle development process is a vehicle program. For a large company, such as the one we studied, there are typically multiple models with different brand names within the same vehicle program. A model refers to the end product that is sold to the customers in dealerships (e.g., Chevrolet Malibu, Toyota Camry, etc.). Although models under the same vehicle program may be sold under different brand names, their underlying architectural structure and product development effort is similar. Because vehicles are built off of platforms, there is a good deal of component commonality across models. Some of these components are entirely new to the program, whereas some are carried over from previous programs. Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture Management Science 56(3), pp. 468–484, © 2010 INFORMS It takes two to three years to complete the entire product development process for a program. A program provides a platform for several vehicles, which are typically launched in a staggered fashion to smooth demands on engineering and marketing resources. Once in the market, vehicles are usually given major refreshes (redesigns) every five to six years, with a minor update at about the midpoint of a model life cycle. Most models are eventually retired after being in the market for several design cycles. For practical reasons of data availability, we followed our client in dividing an automobile into 243 architectural subsystems, which contain roughly 150,000 parts that interact with each other. Consequently, we will construct the product architecture network by describing interfaces between subsystems. 3.2. Organization The primary actors in a vehicle development organization are design engineers. Although other types of engineers (e.g., materials engineers, quality-control engineers, and testing engineers) are employed by the organization, their direct involvement in the design process is limited. Therefore, we focus our attention exclusively on the design engineers. In the system we studied, there were about 10,000 engineers who participated in the engineering design work. These engineers are responsible for creating the parts, making sure that they meet design specifications and coordinating interfaces with other parts. Design engineers typically work in groups of 5–10 people, led by a manager who is responsible for supervising the design of parts and components, as well as coordinating efforts within and beyond the group. Within the product development system, design engineers coordinate with each other through distribution lists. Whenever there is activity related to a part, designated engineers who are directly involved (e.g., an engineer whose parts share a direct physical interface with a modified part) or indirectly involved (e.g., an engineer whose part shares an indirect functional interface) are notified via the distribution list. Individual engineers are placed on these distribution lists as a result of both management policy and requests by engineers. As such, distribution lists capture both formal connections inherent in the organization chart and informal connections that emerge from the experience of engineers. 3.3. Information System and Engineering Change Orders Because of significant advances in computer data storage and processing capacities, firms are able to accumulate and track large amounts of data about the product development process. In our study, we made use of an ECO system like that used in most product development processes as a tool to control and document the product development process. (For a 471 detailed overview of ECO systems, see Loch and Terwiesch 1999.) An ECO is filed by a design engineer every time a new part is released or an existing part is changed in any way. Although the details vary from one company to another, the basic features of most ECO systems are similar. In our client’s vehicle design process, the ECO database contained approximately 100,000 separate ECOs for one model year. A typical ECO contains the identity of the engineer who initiated it, a unique reason code that explains why the ECO was issued, the identities of other engineers to be notified as part of a distribution list about activity related to the ECO, part numbers associated with it, and the targeted and actual dates of completion. Figure 1 shows a simplified version of our client’s ECO process. Note that there are several different situations for which ECOs are created, including when a part is initially released, when there is a design problem that must be corrected, and when there is an exogenous change (e.g., because of a government regulation, styling change, or supplier request). Each ECO is notated with a reason code, which describes the specific motivation for it. For purposes of analysis, we have grouped ECOs into three mutually exclusive sets according to their reason codes: (1) new release ECOs, which are filed for all parts of a new model (note that some of these parts are new, whereas others are existing parts from a previous model that have been renumbered for the new model); (2) problematic ECOs whose reason codes were identified by several design engineers with whom we consulted as indicating problems in the design process; and (3) other ECOs, which include all ECOs not contained in the above categories (e.g., ECOs due to a cost reduction initiative or a change in government regulations). The role of each of these ECO types in the design process are illustrated schematically in Figure 2. We use this classification to create variables in the empirical model in the next section. There have been several studies (see Clark and Fujimoto 1991, Huang and Mak 1999, Terwiesch and Loch 1999, Loch and Terwiesch 1999) of ECOs in the design process. These examined the broad significance of ECO generation without specifically capturing product architecture information or organizational structure. Because ECOs are filed when an individual part fails to meet specifications, two or more parts have interface problems, or product changes are made that affect part designs, the ECO database contains a great deal of information. To our knowledge, this study is the first attempt to use the ECO system to capture product and organization interactions. Previous studies (e.g., Sosa et al. 2004, 2007) have relied on surveys to construct networks for both product architectures and organizational structures. This is (a) time consuming, which may limit use in practice, Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture 472 Figure 1 Management Science 56(3), pp. 468–484, © 2010 INFORMS A Schematic of ECO Flows in the Vehicle Design Process Design engineer/group manager Sample reasons for issuing an ECO • New release • Performance test failure • Cost reduction • Government regulation, etc. Discuss, draft and pre-approve ECO Responsible engineer • Identify engineers who need to be notified in the distribution list • List related part numbers • Specify dates of completion Responsible engineer Other engineers on the distribution list Incorporate necessary changes to owned parts and sign off Perform necessary changes and modifications Group manager Approve changes and sign off Not resolved Change approval: cross system, cross functional board Resolved and (b) subject to people’s memories (e.g., a vehicle program lasts several years, so people must remember with whom they collaborated years ago to construct a relevant organizational structure network through a survey). Because the ECO system contains information about both parts and the engineers who work on them, we can use it instead of surveys to construct the Figure 2 product architecture and organizational coordination networks. 4. Model Development In this section, we describe how we created the product architecture and organizational coordination networks from the ECO data described above. These networks Modification of a Part Through the ECO System Problematic ECO Design/Integration problems Part release New release ECO Pass Design Test Other problems Other ECO Launch Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture Management Science 56(3), pp. 468–484, © 2010 INFORMS Figure 3 473 Product Architecture Network: A Network of Vehicle Subsystems are the basis for the key independent variables in our empirical study of vehicle quality. So, once we have described the networks, we discuss the construction of the dependent variable, independent variables, and control variables in our regression model. 4.1. Creating the Product Architecture Network We constructed the product architecture network by defining vehicle subsystems as nodes. We defined links between these nodes by looking only at new release ECOs. Note that these new release ECOs are not a result of a problem or later changes, but purely a result of initiating all parts of a new vehicle program. As such, they provide an unbiased summary of the linkages between parts. For example, when a part in the steering wheel subsystem is newly released, all parts related to it, which may be in the steering wheel, electrical traction, or other subsystems, will be automatically listed on the new release ECO for that part. The logic behind this construction is straightforward: When a part is initiated by issuing a new release ECO, all parts that share some sort of physical or functional interface with that part are also listed in the ECO. Therefore, if we look at all such ECOs and count how many times two subsystems appear in the same ECO, we can get a proxy for the strength of the architectural interaction (number of interfaces) between the two subsystems. Specifically, we use the number of new release ECOs that include parts both from subsystems i and j as the weight for the link between nodes i and j in the product architecture network. This network reveals that the various subsystems differ substantially in terms of their connections to other subsystems. For example, in a car, the wiring harness subsystem has physical connections to almost every other subsystem, while the air cleaner subsystem has only a limited number of physical connections with the rest of the vehicle. Figure 3 depicts a visual representation of the product architecture network, which shows that the network is too large and complex to analyze visually. Clearly, we need quantitative metrics to characterize the product architecture in a useful manner. 4.2. Creating the Organizational Coordination Network Many organizational studies (see Ibarra 1993, Krackhardt and Hanson 1993, Burt 2004) have studied communication and advice networks of individuals by using empirical data sets that are usually collected through surveys or questionnaires. Our study differs from these by making use of formal institutional connections, rather than informal social ones. One benefit of this approach is that it permits organizational analysis with data already being recorded, and so does not subject the organization to the burden of a detailed survey. A second benefit is that it focuses on links over which management has a great deal of influence (i.e., who is listed on which distribution list). Hence, any levers indicated by this analysis can be translated into concrete management policies. To construct the organizational coordination network, we again used vehicle subsystems as nodes and proceeded in two steps. In the first step, we used only the new release ECOs to determine which engineers are associated with which subsystems. We did this because our client indicated that only key engineers 474 Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture involved in the design of the parts (and hence subsystems) are listed in the new part release ECOs. (Note that an engineer may be associated with more than one subsystem, while a subsystem always involves more than one engineer.) In the second step, we used all ECOs to characterize communication between subsystems, to capture the full range of communication over the duration of the project. Specifically, we used the number of distribution lists that include engineers from both subsystem i and subsystem j as the weight of the link between nodes i and j in the organizational coordination network. Note that each distribution list corresponds to an issue in the product development work, so we count the number of distribution lists rather than the number of people in establishing the links between subsystems. 4.3. Scope of the Model We tested our hypotheses by developing a regression model. We examined 13 vehicle programs, with 243 subsystems in each, giving us a total of n = 243 × 13 = 3159 observations in the model. Each of the 13 programs corresponded to a 2005 model-year vehicle designed in the United States and sold solely to U.S. customers. Note that these programs correspond to platforms from which many models are introduced. For example, our client launched 32 distinct models in the 2005 model year. As the dependent variable in the model, we used warranty claims data aggregated from roughly 17,000 unique problem codes up to the subsystem level. We followed our client in using IPTV (incidents per thousand vehicle) as a measure of quality. We used the number of warranty incidents (IPTV) reported during the first 12 months after the vehicle launch. Note that we observed warranty data during the first year of the vehicle use (i.e., in calendar years 2005 and 2006), but the ECOs that describe the product and organization networks for these programs were initiated during calendar years 2002–2005. Therefore, collecting design and quality data for one model year requires examining over four years of data within the company. We conducted a similar study by examining the vehicles that were launched in the 2006 model year to check the robustness of the model. As before, we focused on 13 vehicle programs, which correspond to 26 distinct models. Because the procedure and the results are very similar to those for the 2005 model year, we present them in the online appendix (provided in the e-companion).1 1 An electronic companion to this paper is available as part of the online version that can be found at http://mansci.journal.informs.org/. Management Science 56(3), pp. 468–484, © 2010 INFORMS Figure 4 Calculating Degree Centrality in the Product Architecture Network Centrality score = 66 Electrical traction 4 Door trim Centrality score = 17 4.4. Centrality score = 44 19 43 13 Steering wheel 25 Wiring harness Centrality score = 9 9 Battery Centrality score: 13 + 43 + 25 + 9 = 90 Independent Variables 4.4.1. Centrality in the Product Architecture Network. After creating the product architecture network as outlined in the previous section, we calculated the centrality scores of the nodes (subsystems) using UCINET 6,2 Borgatti et al. (2002). We use degree centrality, which is computed as the sum of the weights of the links emanating from a node to characterize the level of connectivity of a subsystem. Subsystems with higher degree centrality have more interfaces and are therefore, presumably, more complex. Figure 4 illustrates this by showing partial centrality scores for a portion of the product architecture network. To look for the U-shaped relationship conjectured in Hypothesis 1, we also included the square of the degree centrality as an independent variable. A positive coefficient for the linear variable and a negative coefficient for the squared variable would suggest an inverted U-shaped relationship between degree centrality and warranty claims. 4.4.2. Coordination Deficit. Hypothesis 2 conjectures that misalignment between the product architecture and organizational structure is associated with quality problems. The product architecture and organizational coordination networks defined above provide a means for quantifying misalignment. But there are many ways to specify and measure mismatches between the two networks. As long as (a) the metric is computed from the data contained in the product architecture and organizational coordination networks, and (b) the metric monotonically increases in the extent to which the two networks are misaligned, then it can be considered as a possible metric. Below, we discuss one such metric that we feel fits the NPD process, along with three other plausible metrics. To develop a misalignment metric, we first posit that the interfaces between two subsystems in the 2 UCINET is a social network analysis software package that graphically displays networks and computes most standard network metrics. Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture 475 Management Science 56(3), pp. 468–484, © 2010 INFORMS product architecture network imply a certain number of design issues that must be resolved. This number may be uncertain, but we assume that it is proportional in expectation to the number of interfaces indicated by the product architecture network. We further assume that each issue requires some number of communications to resolve, which again may be uncertain. The product of these two numbers is the number of communications required to successfully coordinate the two subsystems. If the number of communications falls short of this limit, then unresolved issues may result in design flaws that lead to warranty claims. Because each unresolved issue represents an additional flaw, we conjecture that the expected number of warranty claims is linearly related to the difference between the actual and required number of communications. However, if the number of actual communications exceeds the required number, then no additional benefit is gained, because communications about the interfaces between subsystems i and j will not impact design issues involving interfaces between other pairs of subsystems. We quantify the above reasoning into a metric that we call the coordination deficit metric. To do this, we let W A and W C represent the product architecture and coordination networks, respectively, where W A = WijA , and WijA represents the weight of the link between nodes i and j in the product architecture network; and W C = WijC , and WijC represents the weight of the link between nodes i and j in the organizational coordination network. Because these weights may have different magnitudes, we normalize them by dividing by the total weight of the links in each network. This yields Aij = WijA / i j WijA /2 and Cij = WijC / i j WijC /2, where Aij and Cij represent the proportion of total links that are from subsystem i to subsystem j in the product architecture and organizational coordination networks, respectively. With these, Figure 5 we define i as the coordination deficit for node (subsystem) i as i = maxAij − Cij 0 (1) j Note that this metric includes only links where Aij − Cij is positive (i.e., the connection between nodes i and j is stronger in the product architecture network than in the organizational coordination network) to capture undercoverage of subsystem linkages. Because problems from lack of coordination cannot be reduced below zero, we would not expect excess coverage along one link to offset inadequate coverage along another. Hence, we omit links where Aij − Cij is negative. Figure 5 illustrates calculation of the coordination deficit metric for a subset of the nodes in the vehicle development system. In this example, the wiring harness subsystem has four links in the product architecture network to the door trim, electrical traction, steering wheel, and battery subsystems, with weights of 13, 43, 25, and 9, respectively (see Figure 5). Because the total weight of all the links in the network is 4 + 19 + 13 + 43 + 25 + 9 = 113, these links represent the following fractions of the total: 0.115, 0.380, 0.221, 0.079. In the organizational coordination network, the wiring harness subsystem has four links to the same nodes as in the product architecture network, with weights of 2, 27, 33, and 7. These represent the following fractions of the total: 0.024, 0.325, 0.397, and 0.084. For each link, we compute the difference between the fraction of weight in the product architecture network and the fraction of weight in the organization network (inserting a zero if this difference is negative). This yields a coordination deficit for the wiring harness subsystem of 0115 − 0024 + 0380 − 0325 + 0 + 0 = 0146. Once we have computed coordination deficit in this manner for all subsystems (nodes), we can use it as an independent variable in our model. An Example of Calculating Coordination Deficit for a Subset of Nodes Product architecture network Electrical traction 19 4 43 25 13 0.380 0.036 Electrical traction 9 Organizational coordination network Door trim 0.115 2 0.221 0.134 Wiring harness Steering wheel Steering wheel 0.079 0.397 Battery 0.036 0.325 11 27 0.169 33 3 7 Door trim 0.024 Wiring harness 0.084 Battery Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture 476 Management Science 56(3), pp. 468–484, © 2010 INFORMS Although our coordination deficit metric is reasonable, it is not the only way to measure mismatches between the product architecture and organizational coordination networks. To see if another measure might work better, we considered three alternatives that also satisfy the two criteria we defined above for a metric to measure misalignment: 1. The ratio metric is computed as the ratio of the percentage of links in the two networks. That is, we first calculate the percentage of the entire network flow at each link for both architectural and coordination networks as we did for the coordination deficit metric (i.e., calculating the Aij and Cij ). However, unlike the coordination deficit metric, which calculates the difference between the flow at links in two networks, this metric calculates the ratio between the flow at links in two networks. After calculating the ratios, it proceeds similar to the coordination deficit metric, and aggregates these ratio values at each node. More formally, the ratio metric for node (subsystem) i is given by Ri = j max Aij Cij 0 (2) Although this metric is monotonic in the degree of mismatch between the product architecture and organizational coordination networks, it implies that reducing the number of mismatches will affect quality (warranty claims) in a nonlinear fashion. 2. The node difference metric is computed as the difference between the centrality score of the subsystem (node) in the product architecture network and that in organizational coordination network. That is, if we let Ai = j Aij be the centrality of node i in the product architecture network, and Ci = j Cij be the centrality of node i in the organizational coordination network, the node difference metric for node (subsystem) i is given by Di = maxAi − Ci 0 (3) As such, this metric considers node differences between the two networks, rather than link differences. 3. The local deficit metric is obtained by calculating the percentage of flow along each link emanating from a node. After calculating these flow percentages at each node for both networks, it proceeds in a fashion similar to the coordination deficit metric and calculates the aggregated deficit scores. Formally, Aij and Cij are now calculated as Aij = WijA / j WijA and Cij = WijC / j WijC . We then aggregate these for node (subsystem) i as Li = j maxAij − Cij 0 (4) Because it normalizes flows at each link by the total flow from that node, rather than total network flow, the local deficit metric is not sensitive to the total amount of coordination effort associated with a subsystem. For example, 1 unit of flow between nodes i and j out of a total flow of 10 units from node i is regarded as equivalent to 10 units of flow between nodes i and j out of a total flow of 100 units from node i. We examined both the original coordination deficit metric and these three alternate metrics in our regression analysis, as we discuss in §5. 4.5. Control Variables 4.5.1. Previous Year’s Warranty Claims. Although we control for all relevant factors for which we could obtain data, there may still be unobserved factors, such as subsystem characteristics or engineer capabilities, that could bias the results. According to (Wooldridge 2002), “Omitted variables bias can be eliminated, or at least mitigated, if a proxy variable is available for the unobserved variable” (p. 63), and “often the outcome of the dependent variable from an earlier time period can be a useful proxy variable” (p. 66). Nerkar and Paruchuri (2005) and Heckman and Borjas (1980) used this approach by introducing previous performance as an independent variable to predict current performance. To control for unobserved factors, we used warranty claims in the previous year as an independent variable. 4.5.2. Fraction of Problematic ECOs. We included the fraction of problematic ECOs as a measure of internal quality problems. The rationale is that the rate of internal quality problems could be a signal of external warranty issues. Because problematic ECOs are a result of design related mistakes, a high percentage of problematic ECOs is a reasonable proxy for the rate of internal quality problems. 4.5.3. Fraction of New Parts. Following Clark et al. (1987), who adjusted for the fraction of new parts in a vehicle to compare the productivity of different auto makers, we include the fraction of new parts (relative to the previous model year) in a subsystem as a control variable. We would expect to experience more quality problems with new parts than old ones. 4.5.4. Other Controls. We also controlled for the following additional factors: • Number of parts: This is the total number of parts in a subsystem, which may be a proxy for the subsystem size or complexity. • Number of engineers: This represents the total number of engineers that appear in the distribution lists associated with a subsystem, which is another potential proxy for the complexity of that subsystem. Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture 477 Management Science 56(3), pp. 468–484, © 2010 INFORMS • Number of ECOs: This is the total number of ECOs that are generated in a subsystem, which may be yet another indicator of the complexity of a subsystem. • Average ECO tardiness: This variable is calculated using the targeted completion dates and actual completion dates of ECOs. Specifically, it calculates the tardiness for each ECO and then averages it across all ECOs in a subsystem. Tardiness could indicate trouble in the design process (bad for quality) or additional time spent resolving problems (good for quality) and so does not have an obvious expected relationship with warranty claims. 5. that varies randomly over programs for each subsystem. While random-effects models make use of the (seldom met) assumption that individual effects are uncorrelated with the regressors, and model individual constant terms as randomly distributed across cross-sectional units, fixed-effects models impose the most powerful control on unobserved heterogeneity by only examining within subsystem variation (Greene 2008). A random-effects model is more appealing to us than a fixed-effects model for two reasons: (i) Fixedeffects models can produce biased estimates for panels over short time periods (Greene 2008, Hsiao 1986). Because we only have 13 programs (similar to having 13 time units) and a large number of cross-sections (N = 243), a fixed-effects model may not be appropriate. (ii) Fixed-effects models provide poor estimates of the effects of the variables that vary only slightly over time (i.e., over the 13 programs) (Kraatz and Zajac 2001). In our panel data, some of the key variables such as number of design engineers and fraction of new parts change only slightly across programs. Random-effects models do not share these limitations. They allow us to examine both within and between subsystem variance in independent and dependent variables. Nevertheless, we fitted both the random-effects model and fixed-effects model, and conducted a Hausman test to determine which specification is more appropriate (Hausman 1978). In this test, under the null hypotheses, the two estimates do not differ significantly, and, therefore, the more efficient and consistent random-effects model is preferable. The Hausman test resulted in a test statistic of 2 = 1174, which is well below the critical value of 15.51 from the chi-squared table. Therefore, the null hypothesis of the “no statistical differences” is not rejected, which implies that the random-effects model is the appropriate specification for our data. Analysis and Results Table 1 shows descriptive statistics and bivariate correlations between the variables in our models. Warranty incidents for the 2004 and 2005 model years are highly correlated as expected. Furthermore, we note that both centrality of a subsystem and coordination deficit have positive correlations with 2005 warranty claims. Our study examines a total of 243 subsystems across 13 vehicle programs. Because we have all subsystems present in all programs, we have the repeated observations for each of the 243 subsystems. This panel structure of our data set (i.e., a cross-section of 243 subsystems observed 13 times) allows us to explore both within and between subsystem variation. By using panel data methods, we can control for the unobserved subsystem characteristics, which could pose a major problem for the ordinary least squares estimates (Petersen and Koput 1991). A fixed-effects model could address the problem of unobserved heterogeneity by including an error term that is assumed to be constant over vehicle programs for each subsystem, whereas a random-effects model could address this by inserting an error term Table 1 Descriptive Statistics Variable description (1) Warranty incidents for 2005 (2) Warranty incidents for 2004 (3) Number of parts (4) Number of design engineers (5) Number of ECOs (6) Fraction of new parts (7) Fraction of problematic ECOs (8) Average ECO tardiness (9) Centrality of a subsystema (10) Centrality squared of a subsystema (11) Coordination deficit a Normalized scores. Mean SD Min Max 4115 2398 0086 11830 1 (1) 4372 2468 0161 13652 0728 2302 1045 13489 28905 164 17 275 221 2322 0332 0284 16861 0158 0053 132 0076 0109 294 0714 0570 2368 0219 0078 5058 0173 0148 0000 0033 0001 0081 0047 0001 (2) (4) 1 0202 1 0317 0034 0067 0389 0108 0074 (5) (6) (7) 1 0065 0087 1 0314 1 (8) (9) 0021 0143 0117 82000 −0112 −0094 0092 −0146 0105 0103 −0116 1 0572 0365 0211 0285 0085 0173 0007 0079 −0084 1 0760 −0288 −0192 −0109 −0022 −0111 −0008 −0071 0069 −0173 0244 0269 (10) (11) 1 0033 0014 −0074 −0085 0059 0165 0133 (3) 0187 0045 −0089 0025 0093 0124 −0118 1 0461 −0297 1 Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture 478 Management Science 56(3), pp. 468–484, © 2010 INFORMS Table 2 Models of Warranty Incidents for Product Subsystems Estimation method: Variable Warranty incidents for 2004 Number of parts Number of design engineers Number of ECOs Fraction of new parts Fraction of problematic ECOs Average ECO tardiness Model 1 Random-effects (controls) Model 2a Random-effects (architecture) Model 2b Fixed-effects (architecture) Model 3a Random-effects (deficit) Model 3b Fixed-effects (deficit) 06943∗∗∗ 0077 00038 0013 −00098 0006 00061 0004 3752∗∗ 1440 1016∗∗ 5041 −0153∗∗ 0059 06881∗∗∗ 0077 00053 0010 −00087∗ 0005 00066 0004 08319∗∗∗ 0126 00084 0019 07024∗∗∗ 0079 00049 0014 08608∗∗∗ 0131 00077 0017 −00125 0008 00039 0006 −00091∗ 0005 00064 0004 −00098 0007 00043 0006 3744∗∗ 1472 9653∗∗ 4890 3108 2140 6741∗∗ 3127 3719∗∗ 1465 9462∗∗ 4851 3325 2144 6722∗∗ 3125 Centrality of a subsystem Centrality squared of a subsystem −0147∗∗ 0064 −0219∗ 0115 378∗∗∗ 0942 −607∗∗∗ 1186 292∗∗∗ 0874 −513∗∗∗ 1143 Coordination deficit R-squared (%) Adjusted R-squared (%) N ∗ 71.00 70.93 3,159 72.55 72.46 3,159 29.53 29.35 3,159 −0116∗∗ 0051 −0236∗ 0121 26975∗∗∗ 0997 23494∗∗ 0922 73.95 73.88 3,159 30.76 30.61 3,159 p < 01; ∗∗ p < 005; ∗∗∗ p < 001. Table 2 presents the results of our panel model. Model 1 consists of only the control variables. As we would expect, this shows that warranty incidents in 2004 is significant (p < 001) as a predictor of warranty incidents in 2005. This confirms that it is an effective proxy variable. Both the fraction of new parts and the fraction of problematic ECOs also have significant positive coefficients (p < 005), which indicates a positive association between these variables and warranty incidents. Average ECO tardiness is significant (p < 005) with a negative coefficient, which suggests that ECOs that take longer to resolve tend to result in fewer quality problems in the field. Finally, the number of parts and the number of ECOs in a subsystem are not significant. This agrees with our onsite observations that (i) subsystems with more parts are not necessarily more complex, because some of the simplest subsystems involve many tiny parts, and (ii) total number of ECOs itself is not a good quality indicator because many ECOs are not problem related. Note that Model 1 explains almost 71% of the variation in 2005 warranty incidents. 5.1. Inverted-U relationship Model 2a adds the linear and quadratic terms for subsystem centrality to investigate Hypothesis 1. We note that both terms are significant, but that the coefficient is positive for the linear term and negative for the quadratic term. Although this is consistent with the conjectured inverted U-shaped relationship, it is not sufficient to demonstrate it. We must also show an appropriate distribution of the independent variable around the maximum. Without this, the coefficients might indicate a monotonic concave relationship instead. The Box-Whisker plot in Figure 6, which provides a simple visualization of the data by dividing the sample into deciles and box-plotting each subsample, also supports the inverted-U relationship. To further check the inverted-U relationship, we performed two calculations (see the online appendix for details): (i) First, we calculated the location of the inflection point (i.e., the maximum), which corresponds to (378 − 2 × 607 × x = 0) or x = 0311. This value is about half a standard deviation above the mean, which supports the inverted-U relationship. (ii) We divided the data into deciles, conducted separate regressions within each subsample, and observed the pattern of the coefficient of subsystem centrality. The estimated coefficients in these separate regressions confirm the inverted-U relationship with the maximum in the seventh decile. We also checked for outliers, because a significant curvilinear relationship between subsystem centrality and warranty incidents might be attributed to a few outliers in subsystem centrality. We did not detect any influential outliers using Cook’s distance (Cook and Weisberg 1982). Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture 479 Management Science 56(3), pp. 468–484, © 2010 INFORMS Figure 6 Box-Whisker Plot for Subsystem Centrality and Warranty Incidents 14 12 q1 Min Median Max q3 Warranty incidents 10 8 6 4 2 0 Decile 1 Decile 2 Decile 3 Decile 4 Decile 5 Decile 6 Decile 7 Decile 8 Decile 9 Decile 10 Centrality deciles Note that the behavior of the control variables is quite similar in Models 1 and 2a. Also note that with the addition of subsystem centrality variables (both the linear and quadratic term), the adjusted R-squared improves from 70.93% to 72.46% despite the loss of two degrees of freedom. Hence, we conclude that Model 2a supports Hypothesis 1 and indicates an inverted-U relationship between subsystem centrality and warranty incidents. 5.2. Coordination Deficit Model 3a replaces the two subsystem centrality variables with our coordination deficit metric as a predictor and shows coordination deficit metric to be highly significant (p < 001) with a positive coefficient. Note that instead of including both subsystem centrality and coordination deficit in the model simultaneously, the coordination deficit variable replaces the subsystem centrality variable. The reason for this is that it is our theory that both variables are proxies for the same effect, namely that mismatches between the organizational coordination network and the product architecture network increase the likelihood of warranty claims. However, subsystem centrality captures this effect only very roughly, by suggesting through the observed inverted-U relationship that intermediate centrality subsystems tend to exhibit higher levels of warranty incidents. In contrast, coordination deficit measures the mismatches much more directly by incorporating information about the organizational coordination network, as well as the product architecture network. That the two variables overlap in their predictive role is supported by the fact that they are correlated (correlation coefficient = 0.461). That they are not identical is supported by the fact that a regression including both subsystem centrality and coordination deficit has both variables significant (at the 5% level). We observe that although the majority of the explanatory power of the model comes from the previous year’s warranty claims, adding the coordination deficit metric to the original control variables causes adjusted R-squared to improve from 70.93% in Model 1 to 73.88% in Model 3a. Hence, Model 3a supports Hypothesis 2 by suggesting that coordination deficit and warranty incidents are positively associated. The fact that R-squared is higher in Model 3a than in Model 2a suggests that coordination deficit is a better predictor of warranty claims than is subsystem centrality. This makes sense because coordination deficit contains much more information about the system than does subsystem centrality. Finally, note that coefficients of the variables are quite stable across models. This supports our earlier observation that multicollinearity is not a problem. But, it also suggests that the magnitudes of the coefficients are a good gauge of the effects. In addition to the three models presented in Table 2, we ran versions of Model 3a using the ratio, node difference and local deficit metrics presented in §4.4.2. However, none of these metrics were significant. Given the logical flaws in these metrics, this is not surprising. The ratio metric assumed a nonlinear relationship between reduction in mismatches and Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture warranty claims, which is hard to defend considering the observation in §4.4.2 that architectural interfaces generate issues requiring communications to resolve, implying a linear relationship between warranty claims and mismatches. The node difference metric is a coarser measure of mismatches than the coordination deficit metric because there are many fewer nodes than links, which explains why it did not work as well in predicting quality problems. Finally, the local deficit metric used the normalization of flows at each node, and did not consider the flows in the other parts of the network. Hence, this metric cannot detect some kinds of misalignment that are detected by the coordination deficit metric, and, consequently, it was less effective. 5.3. Checking for Endogeneity and the Robustness of Results Because some of the covariates in our models include measures that are potentially endogenous (e.g., assignment of distribution lists, etc.), it is important to examine potential endogeneity issues and their impact on the results. Although the Hausman test suggested that a random-effects model is appropriate for our data, we also examined the results of the fixed-effects model, which specifically controls for the unobserved heterogeneity. We present the results of the fixed-effects regressions in Models 2b and 3b. Note that the coefficients and significance levels of the variables in these fixed-effects models are different than those in the earlier random-effects models due to different model assumptions. Also, because the fixed-effects models only exploit within subsystem variation, the R2 values are significantly lower than the random-effects models. The main conclusion from Models 2b and 3b is that our main variables of interest, product network centrality and coordination deficit, are significant at the 0.01 and 0.05 levels, respectively. This provides further support for our earlier results. One significant variable that may be effected by such endogeneity problem is coordination deficit. To examine the endogeneity of coordination deficit, we created a two-stage least squares (2SLS) randomeffects model (Baltagi 2001). In this procedure, in the first stage we regress all exogenous variables on the suspected endogenous variable (i.e., coordination deficit) and get the fitted values. Here we use number of new release ECOs, number of new release parts, and number of engineers working on new release parts as the instruments. We expect these variables to have a direct effect on coordination deficit, but no effect on warranty claims other than their indirect effect through coordination deficit. We then calculate the second stage model using the fitted values created in the first stage. The results of the 2SLS random-effects model showed that all pairs of coefficients are within Management Science 56(3), pp. 468–484, © 2010 INFORMS Figure 7 Organizational Coordination vs. Product Architecture Centrality 0.40 Organizational coordination centrality 480 y = 1.114x 2 – 0.249x + 0.072 0.35 R 2 = 0.471 0.30 0.25 0.20 0.15 0.10 0.05 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Product architecture centrality a 90% confidence interval of the original randomeffects model, suggesting that endogeneity does not pose a threat for our analysis. Results of Model 2a in Table 2 support the proposed inverted-U relationship between product architecture centrality and warranty claims. As mentioned in §2, one potential explanation of this relationship could be as follows: It may be hard for organizations to gauge and provide the right amount of attention to intermediate central subsystems, but it is probably easier to identify highly central subsystems and provide sufficient resources accordingly. If this is the case, then we should observe fewer warranty claims on highly central subsystems than on subsystems with intermediate centrality. To explore this further, we investigated the relationship between product architecture centrality and organizational coordination centrality. As we see in Figure 7, there is very little difference between the organizational coordination centrality for subsystems with product architecture centrality below 0.25, suggesting that the firm does not distinguish between the complexity of these subsystems when making decisions that affect coordination activities. However, for subsystems with product architecture centralities above 0.25, organizational coordination centrality increases very rapidly (i.e., consistent with an increasing convex function), suggesting that these high centrality subsystems receive extensive coordination attention. These observations support our reasoning behind Hypothesis 1 that intermediate centrality subsystems may not be receiving coordination effort commensurate with their complexity. From the results of the models in Table 2, it is clear that warranty claims in the previous year has a large impact on the warranty claims this year. To check the robustness of coefficients of the other variables in the models, we removed this lagged variable from the models and and reran the statistical analysis. We did not observe a significant change in the direction or impact of the coefficients, but as expected, the overall explanatory power of the models were reduced Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture Management Science 56(3), pp. 468–484, © 2010 INFORMS (e.g., adjusted R-squared of Model 2 was reduced to around 11% from 69%) by excluding of the lagged variable. 5.4. Economic Significance of Coordination Deficit In addition to the statistical analyses, we conducted an analysis of economic significance to get a sense of the magnitude of the association between coordination deficit and warranty claims. Following the convention used in other studies (see Nerkar and Paruchuri 2005, Song et al. 2003), we computed the percentage of change in the dependent variable (i.e., warranty claims) associated with a one standard deviation change in the independent variable (i.e., coordination deficit), evaluated at the mean of the data. Reducing coordination deficit by one standard deviation (which is equal to 0047) from the mean in our model predicts a 26975 × 0047 = 0127 unit reduction in warranty claims, which represents a 0127 ÷ 4115 = 308% reduction. For our client, this would translate into millions of dollars annually in direct savings, plus an important reputational benefit (i.e., because Consumer Reports and other rating services consider warranty claims in their evaluation and recommendation of vehicles). Although a 308% reduction in warranty claims is economically important, the percentage of quality issues that are related to coordination deficit may actually be substantially larger than this. The reason is that in our model, the variable representing warranty claims from the previous year may also contain claims that are associated with coordination deficit (i.e., design flaws that were introduced in previous years and carried over to this year’s model through part reuse). So, if the firm were to reduce coordination deficit by one standard deviation in each design cycle, some of the quality improvements would carry over to future vehicles (through components based on previous designs). Although one cannot calculate this carryover effect of the reduction in coordination deficit with precision, we can get an approximate figure by using our models. One way to estimate the potential magnitude of an ongoing reduction in coordination deficit is to make use of Model 3 as follows: First, we note that the regression equation we have is in the following form: warranty claims in year t + 1 = 0 + 1 warranty claims in year t + · · · where t = 2004, t + 1 = 2005, and 1 = 070. Then, we suppose that 1 remains constant over time and that we reduce coordination deficit by x% in each design 481 cycle. (Recall that redesigns occur every five to six years.) If we let yn = total percentage of reduction (both direct and indirect) in warranty claims in the nth redesign and we assume that warranty claims are constant between redesigns, then the total reduction in a given cycle will be equal to the direct reduction plus carryover, which is y1 = x y2 = x + 070x y3 = x + 070x + 0702 x (5) ··· 2 yn = x + 070x + 070 x + 0703 x + · · · + 070n−1 x As n → , this geometric series converges to x + x070/1 − 070 = 333x. So, if coordination deficit is reduced by one standard deviation (i.e., x = 308%), and if there is no redesign at all, then the percentage of warranty reduction in the nth year converges to 333 × 308% = 1026% when n is large. If, instead, we assume that because of technology change and model retirement, the dependence on old designs extends back only five design cycles, then an ongoing one standard deviation reduction in coordination deficit ultimately results in a y5 × x (=294 × 308% = 906%) reduction in warranty claims. To get a sense of the total number of warranty claims that are associated with mismatches between the organizational coordination and product architecture networks (as opposed to the improvement predicted by our model for a realistically achievable one standard deviation reduction in coordination deficit), we consider the predicted impact eliminating coordination deficit entirely. According to Model 3, this would result in a 53% direct reduction in warranty claims, which would yield a reduction of 333 × 53% = 1765% in the limit, and a reduction of 294 × 53% = 1558% if the carryover effect is limited to five design cycles. Although these calculations give us a general sense of the impact of ongoing reduction in coordination deficit, we should be cautious in interpreting the individual coefficients and carryover effects. In the above calculations, warranty claims from the previous year is a proxy variable, which may include many causal effects, of which coordination deficit is only one. Using our regression model to estimate the amount of this variable that is attributable to coordination deficit is reasonable, but far from precise. Moreover, because we would expect design flaws from prior years to get corrected over time, our estimate is probably an upper bound on the overall economic impact of coordination deficit reductions on warranty claims. Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture 482 Management Science 56(3), pp. 468–484, © 2010 INFORMS According to a 2006 J.D. Power and Associates quality survey, an average of 52 of the 124 (i.e., 42%) of quality problems observed in automobiles were design defects (Jensen 2006). If that is true, then our analysis suggests that almost half of these design related warranty claims are due to organizational coordination problems. The rest, presumably, are associated with individual errors. Along with the cost savings, these numbers also indicate a major potential reputational benefit. For example, in a recent J.D. Power and Associates initial quality survey, Toyota observed 104 complaints per 100 vehicles (fourth in ranking), while Honda observed 110 (seventh in ranking), Ford observed 112 (eighth in ranking), and Chevrolet observed 113 problems (tenth in ranking) in the first 90 days of ownership (Bennett and Boudette 2008). Although these complaints are not the same as our warranty incidents, they are certainly related. Because these numbers are very close for the brands, a 10% reduction could move a brand from tenth place to third place. So, relatively small improvements in warranty incidents could make a significant improvement in a firm’s quality rankings and hence its reputation. 6. Discussion Our analysis shows that warranty claims in the previous year have significant power for predicting warranty claims this year. Indeed, when we use only the previous year’s warranty claims in a simple regression, it explains about 55% of the variation in this year’s warranty claims. Though intuitive, this result is not of great managerial use, because it merely implies that trouble spots in a vehicle tend to persist over time. In this sense, using last year’s warranty claim data to predict this year’s warranty claims is a bit like using yesterday’s weather to predict today’s weather. There is a substantial correlation, but the model is obvious. Only by going beyond this level of prediction can we derive useful forecasts. We also observed a positive correlation between the fraction of problematic change orders and the number of warranty claims. Subsystems for which we observe a high percentage of problems during design are the very subsystems that result in a higher number of warranty incidents. The implication is that engineers fix some of the design problems by issuing and resolving ECOs, but not all of them. Because some design problems reach the marketplace and lead to warranty claims, management efforts to reduce the problematic change orders will both speed the vehicle development process and improve vehicle quality. Another factor shown by our analysis to be correlated with warranty claim incidents is the percentage of new parts in a subsystem. This is intuitive given the learning involved in the design of a new part. From a management perspective, this implies that design organizations should devote extra attention and resources to subsystems with higher fractions of new parts. Although our client clearly knew this already, the fact that warranty claims are still positively correlated with the fraction of new content suggests that current levels of attention and/or resources may not be enough. A somewhat counterintuitive implication of our results is that tardiness of engineering change orders and quality problems are negatively correlated. Although one might expect tardiness to compromise quality (e.g., by causing haste or chaos in the design process), we observed that subsystems with more ECO tardiness tend to have fewer quality problems in the field. This may be due to a simple time versus quality trade-off; more time on a component results in a lower probability of a problem, even at the expense of missing due dates. Of course, while missing a due date in order to spend more time on a given component may improve that component, it may also be detrimental to other components or the vehicle launch as a whole. So, although this result may suggest that management should be careful about compressing design times too much, it certainly should not be taken as support for missing due dates established by the ECO system. The inverted-U association we observed between subsystem centrality and warranty incidents suggests that subsystems of intermediate centrality are more prone to quality problems. We conjecture that this is because intermediate centrality parts are more difficult to evaluate with regard to their complexity than are high centrality parts (which are obviously complex) or low centrality parts (which are obviously simple). As such, it is more difficult to determine the appropriate amount of resources and coordination effort for intermediate centrality parts than for either high or low centrality parts. Though intriguing from a research perspective, this result does not identify specific subsystems in need of greater attention and hence is of limited managerial use. Our most important contributions are (1) introducing the coordination deficit metric for quantifying mismatches between the product architecture and the organizational structure, and (2) showing that this metric is positively correlated with warranty claim incidents. This result is significant to the literature on network analysis of product development systems because (a) it is the first effort to formally measure misalignment between an organization and its assigned work, and (b) it provides support for the common conjecture that misalignment of the design organization with the product architecture is detrimental to performance. From a management perspective, this work suggests some potentially appealing insights. First, our Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture Management Science 56(3), pp. 468–484, © 2010 INFORMS analysis highlights a means for mining ECO system data to monitor the alignment of the organization with the product being designed. Our coordination deficit metric provides a simple quantitative measure of the degree of mismatch and points out specific pairs of subsystems where the level of formal coordination is less than the extent of connectivity in the product architecture. Such pairs of subsystems may be candidates for additional coordination attention. Because the coordination deficit metric also identifies pairs of subsystems where the level of coordination activity exceeds the amount of connectivity in the product architecture, it may also suggest places where coordination efforts can be reduced with minimal impact on performance. This suggests that it is possible to improve the match between organizational coordination and the product architecture without increasing the total amount of coordination activity. Although the statistical correlations we have identified in this study only suggest, rather than prove, causality, the existence of a positive association between coordination deficit and quality problems is of managerial interest. Because of the large cost of design quality problems (e.g., recalls), managers of product development organizations must be sensitive to any factor that may have an impact on design quality problems. No statistical study (e.g., of the type used in Six Sigma programs) can ever provide proof of causality, so managers can only pursue improvements by addressing factors shown to be associated with quality problems. Our paper introduces and quantifies coordination deficit as one such factor. Furthermore, because researchers and practitioners have been arguing (indeed assuming) that alignment of the organization with the product is desirable, our findings are consistent with current management theory. Our results support this theory and provide concrete guidance on how to act upon it in practice. 7. Conclusions In this paper, we have presented an empirical model that characterizes the misalignment of the product architecture and organizational interactions and have investigated the impact of this misalignment on quality (measured by warranty claims) in a vehicle development process. Our results suggest that organizational factors and product architecture have a significant impact on quality. Our analysis made use of data from an ECO system like that used in most product development processes. These data enabled us to specify both product architecture and organizational coordination networks. As such, our study is the first, of which we are aware, that bases a network analysis of the product development process entirely on standard 483 data from a firm’s information system. Because we do not rely on cumbersome and time consuming surveys, our methodology is more likely to find use in practice than survey based methods. Our work, along with the other studies that have made use of emerging tools of complex networks to characterize both product architecture (a network of components) and organizational structure (a network of people), highlight the potential importance of such network tools to the science and practice of NPD. Our results suggest that misalignment of the design organization with the product architecture negatively affects product quality and uses network tools to highlight the specific areas of misalignment. Sosa et al. (2004, 2007) suggest that such misalignments are influenced by various features of the organizational structure and use network tools to characterize these features. Because of the power and flexibility of these network tools, they are already becoming a standard part of the NPD research tool kit. We expect them to become similarly prevalent as practical management tools in the future. To further the science and practice of NPD processes, this work could be extended in several directions. First, our research exclusively relied on archival (e.g., ECO, warranty) data. Although this is of substantial practical use, because it captures formal connections, it leaves out informal connections, such as communication outside the channels indicated by the distribution lists. Hence, a complementary study could make use of surveys or e-mail and phone records to characterize informal communication for use as an additional predictor of quality performance. A second dimension along which our model could be refined is the granularity of the product data. We have performed our analysis at the subsystem level. This was largely because our client only had warranty claims data that could be appropriately aggregated at this level. However, we could obtain warranty claims at the part level, we could perform a much more detailed analysis of the impact of coordination deficit on product quality. Our expectation is that this would facilitate more precise matching of the organizational structure to product architecture. It would also enable a more accurate prediction of potential quality trouble spots. Finally, we note that the ultimate managerial purpose of this type of analysis is to better adapt the design organization to the products being developed. Our results provide an approach for identifying gaps between organizational structure and product architecture. However, we have only analyzed vehicle programs for one model year. To get a deeper understanding of how vehicle architectures evolve over time and where the organizational coordination practices lag behind product changes, it would be useful Gokpinar, Hopp, and Iravani: Impact of Misalignment of Organizational Structure and Product Architecture 484 Management Science 56(3), pp. 468–484, © 2010 INFORMS to perform a longitudinal study over multiple model years. Although getting data extending back across multiple design cycles would be a huge challenge, such an analysis would represent an important step in the use of complex network methods to further the science of product development. 8. Electronic Companion An electronic companion to this paper is available as part of the online version that can be found at http:// mansci.journal.informs.org/. 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Carey School of Business, Arizona State University, Tempe, AZ 85287, United States a r t i c l e i n f o Article history: Received 26 October 2009 Received in revised form 5 November 2010 Accepted 10 November 2010 Available online 18 November 2010 Keywords: Supply networks Supply chain management Second-tier suppliers Social network analysis Network structure Structural analysis Network indices a b s t r a c t A system of interconnected buyers and suppliers is better modeled as a network than as a linear chain. In this paper we demonstrate how to use social network analysis to investigate the structural characteristics of supply networks. Our theoretical framework relates key social network analysis metrics to supply network constructs. We apply this framework to the three automotive supply networks reported in Choi and Hong (2002). Each of the supply networks is analyzed in terms of both materials flow and contractual relationships. We compare the social network analysis results with the case-based interpretations in Choi and Hong (2002) and conclude that our framework can both supplement and complement case-based analysis of supply networks. © 2010 Elsevier B.V. All rights reserved. 1. Introduction Supply chain management has focused on linear relationships of buyers and suppliers (Cox et al., 2006; Zhu and Sarkis, 2004). While a linear perspective may be useful for planning certain mechanical aspects of transactions between buyers and suppliers, it fails to capture the complexity needed to understand a firm’s strategy or behavior, as both depend on a larger supply network that the firm is embedded in (Choi and Kim, 2008). A firm’s “supply network” consists of ties to its immediate suppliers and customers, and ties between them and their immediate suppliers and customers, and so on (Cooper et al., 1997; Croxton et al., 2001). In the past decade there has been increased discussion of the benefits of adopting a network perspective in supply chain management research (Choi et al., 2001; Lazzarini et al., 2001; Lee, 2004; Wilding, 1998). From a supply network perspective, the relative position of individual firms with respect to one another influences both strategy and behavior (Borgatti and Li, 2009). In this context, it becomes imperative to study each firm’s role and importance as derived from its embedded position in the broader relationship structure (Borgatti and Li, 2009; DiMaggio and Louch, 1998). For example, Burkhardt and Brass (1990) and Ibarra (1993) claim that power and influence derive from a firm’s structural position in its surrounding network. Others have linked network position to such issues as ∗ Corresponding author. Tel.: +1 912 478 2465; fax: +1 912 478 2553. E-mail address: [email protected] (Y. Kim). 0272-6963/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.jom.2010.11.001 innovation adoption (e.g., Burt, 1980; Ibarra, 1993), brokering (e.g., Pollock et al., 2004; Zaheer and Bell, 2005), and creating alliances (e.g., Gulati, 1999). To date, there have been few studies of real-life supply networks, due to the difficulties in obtaining data. The studies of real networks that have been done have relied on qualitative methods to derive theoretical and practical insights (e.g., Harland et al., 2001; Jarillo and Stevenson, 1991). While qualitative interpretations have their merits, their validity is threatened by a researcher’s bounded rationality, which includes the difficulty to conceptualize complex phenomena such as networks. Thus in this paper we propose to analyze the structural characteristics of supply networks using a formal, quantitative modeling approach—social network analysis (Borgatti and Li, 2009; Grover and Malhotra, 2003; Harland et al., 1999). We will show how social network analysis can both supplement and compliment more traditional, qualitative interpretation methods when analyzing cases involving supply networks. Social network analysis (SNA) has recently gained acceptance among scholars for its potential to integrate the operations and supply management field with other branches of management science (Autry and Griffis, 2008; Borgatti and Li, 2009; Carter et al., 2007). According to Borgatti and Li (2009), SNA concepts are particularly suitable for studying how patterns of inter-firm relationships in a supply network translate to competitive advantages through management of materials movement and diffusion of information. To date, SNA has not been applied in an empirical study of real supply networks; in fact there is a general paucity of SNA appli- Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 cations in operations and supply management, with only a few exceptions (e.g., Carter et al., 2007; Choi and Liker, 1995). This is largely because there is lack of conceptual clarification as to how the key SNA metrics (e.g. centrality) can be theoretically interpreted in the context of supply networks. Therefore in this study we link different SNA metrics at the node- or firm-level to specific roles in a supply network. We consider supply networks based on both materials flow and contractual relationships. The metrics yield six supply network related constructs: supply load, demand load, operational criticality, influential scope, informational independence, and relational mediation. Different network-level SNA metrics are also linked to their implications for supply network performance. We apply our framework to real supply network data derived from three published case studies of automotive supply networks (Choi and Hong, 2002). In that study the authors created empirically three complete network maps of the center console assembly for Honda Accord, Acura CL/TL, and DaimlerChrysler Grand Cherokee. In the present paper, we convert the network data from Choi and Hong (2002) into matrix forms and analyze them using the software UCINET 6 (Borgatti et al., 2002). These quantitative results are then interpreted using our theoretical framework. Finally, we discuss our quantitative SNA results comparing to the qualitative findings of Choi and Hong (2002) and consider the implications. 2. Literature review 2.1. Supply networks Supply networks consist of inter-connected firms that engage in procurement, use, and transformation of raw materials to provide goods and services (Lamming et al., 2000; Harland et al., 2001). The relatively recent incorporation of the term “network” into supply chain management research represents a pressing need to view supply chains as a network for firms to gain improved performance, operational efficiencies, and ultimately sustainable competitiveness (Corbett et al., 1999; Dyer and Nobeoka, 2000; Kotabe et al., 2002). Therefore, it is increasingly important to analyze the network structure of supply relationships. In the operations and supply management field, a complex system perspective has been used as a theoretical lens for describing supply networks. Wilding (1998) studied dynamic events in supply networks through what he referred to as “supply chain complexity triangle” (p. 599). Choi et al. (2001) conceptualized supply networks as a complex adaptive system (CAS). Surana et al. (2005) proposed how various complex systems concepts can be harnessed to model supply networks. Pathak et al. (2007) discussed the usefulness of CAS principles in identifying complex phenomena in supply networks. Others have examined supply networks from a strategic management perspective. Greve (2009), using supply networks in the maritime shipping industry, studied whether technology adoption is more rapid in centrally located network positions. Mills et al. (2004) suggested different strategic approaches to managing supply networks depending on whether a firm is facing upstream or downstream and whether it is seeking its long-term or short-term position in the supply network. Methodologically, simulation models have been used to study hypothetical supply networks (Kim, 2009; North and Macal, 2007; Pathak et al., 2007). Others have studied real-world supply networks using the case study approach (Jarillo and Stevenson, 1991; Nishiguchi, 1994; Choi and Hong, 2002). Scholars in the industrial marketing have developed descriptive models of supply networks (Ford, 1990; Håkansson, 1982, 1987; Håkansson and Snehota, 1995). Descriptive case studies in this genre illustrate how companies such as Benetton, Toyota, or Nissan attained competitive advantage through their supply networks (Jarillo and Stevenson, 195 1991; Nishiguchi, 1994). Other studies focused on developing taxonomies of supply networks (Harland et al., 2001; Lamming et al., 2000; Samaddar et al., 2006). More recently, Borgatti and Li (2009) have highlighted the salience of SNA to study supply networks. In fact, there have been a few studies in the operations and supply management field that used or promoted the use of SNA. Choi and Liker (1995) used SNA to investigate the implementation of continuous improvement activities in automotive supplier firms. Carter et al. (2007) provided an example of the application of SNA in a logistics context. Autry and Griffis (2008) applied the concept of social capital, framed as part of social network theory, to supply chain context. However, still lacking in such studies is a theoretical framework that relates social network theory to supply network dynamics and the comprehensive application of SNA to studying supply networks. In the following section, we provide a brief overview of SNA, focusing on the key metrics useful for investigating and explaining phenomena within supply networks. 2.2. Social network analysis (SNA) A network is made up of nodes and ties that connect these nodes. In a social network, the nodes (i.e., persons or firms) have agency in that they have an ability to make choices. With its computational foundation in graph theory (Cook et al., 1998; Kircherr, 1992; Li and Vitányi, 1991), SNA analyzes the patterns of ties in a network. Naturally, SNA has been used to study community or friendship structure (Kumar et al., 2006; Wallman, 1984) and communication patterns (Koehly et al., 2003; Zack and McKenney, 1995). It has been adopted to explore the spreading of diseases (e.g., Klovdahl, 1985) and diffusion of innovation (e.g., Abrahamson and Rosenkopf, 1997; Valente, 1996). In organization studies and strategic management, scholars have used it to investigate corporate interlocking directorships (Robins and Alexander, 2004; Scott, 1986) and network effects on individual firms’ performance (e.g., Ahuja et al., 2009; Burkhardt and Brass, 1990; Gulati, 1999; Jensen, 2003; Rowley et al., 2005; Stam and Elfring, 2008; Uzzi, 1997). Operations and supply management scholars have also noted the methodological potential of SNA. For instance, Choi et al. (2001) stated that one could approach the study of supply networks from the social network perspective. Ellram et al. (2006) acknowledged social network theory as a useful tool to study influence in supply chains. Carter et al. (2007) identified SNA as a key research method to advance the fields of logistics and supply chain management. More recently, Borgatti and Li (2009) and Ketchen and Hult (2007) echoed such sentiments. They have also recognized the difficulty of collecting network-level data in supply networks but argued its imperativeness for operations and supply management to be integrated with other management disciplines. According to Borgatti and Li (2009), a more systematic adoption of SNA will be instrumental in exploring behavioral mechanisms of entire supply networks. A SNA approach allows us to better understand the operations of supply networks, both at the individual firm level and network level—how important the individual firms are, given their positions in the network and how the network structure affects the individual firms and performance of the whole network. Social network scholars (Everett and Borgatti, 1999; Freeman, 1977, 1979; Krackhardt, 1990; Marsden, 2002) have developed a range of network metrics at the node- or network-level to characterize the dynamics inside a social network. 2.3. Key network metrics Network metrics can be calculated at two levels—the node level and network level. Node-level metrics measure how an individual node is embedded in a network from that individual node’s 196 Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 perspective. In this study, we focus on three types of node-level metrics—degree, closeness, and betweenness centrality. Networklevel metrics compute how the overall network ties are organized from the perspective of an observer that has the bird’s eye view of the network. The network-level metrics we consider are network density, centralization, and complexity. 2.3.1. Node-level metrics Identifying the key actors in a social network is one of the primary uses of SNA (Tichy et al., 1979; Wasserman and Faust, 1994). The concept of centrality is fundamental to node-level network metrics (Borgatti and Everett, 2006; Borgatti and Li, 2009). Centrality reflects the relative importance of individual nodes in a network. A node’s central position in a social network has a significant impact on its and others’ behaviors and well-beings (Mizruchi, 1994). Centrality has been associated with social status (Bonacich, 1972; Freeman, 1979), power (Coleman, 1973), and prestige (Burt, 1982). There are different types of centrality metrics and they identify nodes that are important, in different aspects. Most prominent are degree centrality, closeness centrality, and betweenness centrality (Everett and Borgatti, 1999; Krackhardt, 1990; Marsden, 2002). Of these, the most straightforward is degree centrality. This concept builds on an observation that the more links a node has the more central it is—when a node is connected to a large number of other nodes, the node has high degree centrality. Due to its greater connectedness with other nodes, a node with high degree centrality would necessarily be more visible in the network (Freeman, 1979; Marsden, 2002). Another centrality concept is closeness centrality. As the term suggests, this metric focuses on how close a node is to all the other nodes in the network beyond ones that it is directly connected to. A node is central if it can quickly reach all the others, and that is why closeness centrality includes indirect ties. This centrality is usually associated with node’s autonomy or independence in social networks (Freeman, 1979; Marsden, 2002)—a node with high closeness centrality has more freedom from others’ influence and higher capacity for independent actions. Such nodes become less reliant on other nodes. Betweenness centrality measures how often a node lies on the shortest path between all combinations of pairs of other nodes. The more a given node connects nodes that would otherwise be disconnected, the more central that node is—other nodes are dependent on this node to reach out to the rest of the network. This metric focuses on the role of a node as an intermediary and posits that this dependence of others makes the node central in the network. As such, the betweenness centrality usually denotes a node’s potential control or influence in the network (Marsden, 2002). A node with high betweenness centrality has a great capacity to facilitate or constrain interactions between other nodes (Freeman, 1979). 2.3.2. Network-level metrics SNA also yields metrics concerning the structure of the overall network, such as network density, network centralization, and network complexity. Network density refers to the number of total ties in a network relative to the number of potential ties. It is a measure of the overall connectedness of a network (Scott, 2000)—a network in which all nodes are connected with all other nodes would give us a network density of one. Network centralization captures the extent to which the overall connectedness is organized around particular nodes in a network (Provan and Milward, 1995). Conceptually, network centralization can be viewed as an extension of the node-level centrality (Freeman, 1979)—if a network had such a highly centralized structure that all connections go through few central nodes, then that network would be high on network centralization. The network with highest possible centralization is one with a star structure, wherein a single node at the center is connected to all other nodes and these other nodes are not connected to each other. Likewise, the lowest centralization occurs when all nodes have the same number of connections to others. Network centralization and network density are complementary. Whereas centralization is concerned with the distribution of power or control across the network, density reflects network cohesiveness. A network that has every node connected with everyone else would have a highest possible density (i.e., density of one). This network would be a highly cohesive network but would have a diffuse and distributed control structure. Network complexity is defined as “the number of dependency relations within a network” (Frenken, 2000, p. 260) and thus would depend on both the number of nodes in the network and the degree to which they are interlinked (Frenken, 2000; Kauffman, 1993). In the context of a supply network, complexity relates to the collective operational burden born by the members in the network (Choi and Krause, 2006). For instance, a large number of units in a system is likely to entail high coordination cost (Kim et al., 2006; Provan, 1983). Further, if these units are highly interdependent, then the collective operational burden would be high and thus more complex at the system level. Network complexity is related to network density and network centralization. First, more complex networks require higher operational burden (Lokam, 2003; Pudlák and Rödl, 1992, 1994). Second, network density is conceptually linked with network complexity because a denser network requires more effort to build and maintain (Marczyk, 2006). Finally, network centralization is associated with network complexity because the highest coordination costs require when every node is connected to all other nodes (i.e., a network with the least centralization) (Pudlák et al., 1988). 3. Conceptual framework for analyzing supply networks 3.1. Two types of supply network There are a number of different ways in which ties can be established between firms in the supply network. For example, a tie might be established between two firms if they were collaborating on a new product development or if they had overlapping board membership or belonged to the same trade organization. In this paper we focus on two types of ties that Choi and Hong (2002) collected data for in their study. Firms can be linked because of the delivery and receipt of materials, or they can be linked through a contractual relationship (Choi and Hong, 2002). In a tree-like structure of materials flow (Berry et al., 1994; Chopra and Sodhi, 2004; Hwarng et al., 2005), the network describes which supplier delivers to which customer. The other type of network is based on contractual relationships. Often, when a buying company wants to control the bill of materials, it engages in directed sourcing, wherein it establishes a contract with a second- or third-tier supplier and directs the top-tier supplier to receive materials from them (Choi and Krause, 2006; Chopra and Sodhi, 2004; Park and Hartley, 2002). In this context, materials flow occurs between two firms who do not have a contract and vice versa. These two types of supply networks, although based on the same set of nodes, can have different network structures and, therefore, different logics and implications (Borgatti and Li, 2009). 3.2. Supply network constructs 3.2.1. Firm-level constructs We now consider the key node-level SNA metrics and discuss how they can be used to interpret different roles in supply net- Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 197 Table 1 Node-level centrality metrics and their implications for supply networks. Network type Centrality metrics Supply network constructs Conceptual definitions Implication for central nodes Description Key capabilities Materials flow Indegree centrality Supply load Outdegree centrality Demand load The degree of difficulty faced by a Integrator firm in managing incoming material flows from the upstream firms The degree of difficulty faced by a Allocator firm in dealing with demands from the downstream firms To put together or transform different parts into a value-added product and ensure it functions well To distribute limited resources across multiple customers, focusing on scale economies Betweenness centrality Operational criticality The extent to which a firm impacts Pivot the final assembler’s operational performance in terms of product quality, coordination cost and overall lead-time. To facilitate or control the flows of supply across the whole network System integration Design/development Architectural innovation Process/manufacturing Quality management Component innovation Out-bound logistics Risk management In- and out-bound logistics Cross-functional integ. Degree centrality Influential scope Closeness centrality Informational independence Betweenness centrality Relational mediation The extent to which a firm has an impact on operational decisions or strategic behavior of other firms in the supply network The extent to which a firm has freedom from the controlling actions of others in terms of accessing information in the supply network The extent to which a firm can intervene or has control over interactions among other firms in the supply network Rolea Contractual relationship a Coordinator To reconcile differences of network members and align their opinions with the greater supply network goals Navigator To explore, access, and collect various information with greater autonomy in the supply network Broker To mediate dealings between network members and turn them into its own advantage Contract management SRM/CRM Information acquisition Strategic alignment with OEM Information processing Strategic alignment with OEM Network role given high centrality. works. Table 1 offers an overview of key centrality metrics, the corresponding supply network constructs, and their implications for network roles in the context of modeling supply networks. We propose this new framework for the interpretation of the SNA metrics in the supply network context. To illustrate these constructs, we first discuss the calculation of key SNA metrics and the essential properties of each. Then, we integrate each key SNA metric separately with the two types of supply networks (i.e., materials flow and contractual relation). We should note that the supply network based on materials flow is directional, whereas the supply network based on contractual relationship is non-directional as legal obligations are mutually agreed and enacted. 3.2.1.1. Degree centrality in supply network. Degree centrality is measured by the number of direct ties to a node. Degree centrality CD (ni ) for node i(ni ) in a non-directional network is defined as: CD (ni ) = xij = j xji j where xij is the binary variable equal to 1 if there is a link between ni and nj but equal to 0 otherwise (Freeman, 1979; Glanzer and Glaser, 1959; Nieminen, 1973; Proctor and Loomis, 1951; Shaw, 1954). To account for the impact of network size g, degree centrality is normalized as the proportion of nodes directly adjacent to ni : CD (ni ) = CD (ni ) . g−1 For comparison purposes, in this study, we convert normalized degree centrality to a 0–100 scale by multiplying by 100. A high degree centrality points to “where the action is” in a network (Wasserman and Faust, 1994, p. 179). Freeman (1979) describes it as reflecting the amount of relational activities, and such activities make the nodes with high degree more visible. For instance, in a non-directional contractual relationship network, the degree centrality refers to the extent to which the firm influences other firms on their operations or decisions as the firm has more direct contacts with others (Cachon, 2003; Cachon and Lariviere, 2005; Ferguson et al., 2005). In contrast, nodes with low degree centrality are considered peripheral in the same network. If a node is completely isolated (i.e., zero degree), then removing this node from the network has virtually no effect on the network. Therefore, a firm who has more contractual ties in the network garners a broad range of influence on others, and at the same time such a firm would often be required to reconcile conflicting schedules or interests between others. For the final assembler, for instance, it would make sense to align with suppliers with high degree centrality. In a directional network of materials flow, the focus is either on the flow initiated (out-degree) or flow received (in-degree). For instance, out-degree centrality of a node is defined as: CD (ni ) = xi+ . g−1 In-degree centrality and out-degree centrality indicate the size of the adjacent upstream tier and downstream tier, respectively. A high in-degree or out-degree can capture transactional intensity or related risks for a firm (Powell et al., 1996). In a materials flow network, in-degree centrality for a firm can reflect the degree of difficulty faced by the firm when managing the incoming material flows. In other words, this metric measures the firm’s operational load coming from the upstream suppliers. A firm with high indegree centrality may serve the role of an integrator, as they are tasked with organizing and incorporating a range of parts from various suppliers to maintain the overall integrity of the product or service (Parker and Anderson, 2002; Violino and Caldwell, 1998). Such members in a supply network are instrumental and vital in carrying out the architectural or technical changes in the current product (Henderson and Clark, 1990; Iansiti, 2000). Out-degree centrality relates to the firm’s level of difficulty in managing the needs of customers. The more direct customers there are in downstream, the more challenging it is for the firm to ensure on-time delivery, cost-effective inventory, and order 198 Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 management for their customers. The number of direct customers is thus positively associated with the operational load related to demand integration and resource allocation (Frohlich and Westbrook, 2002). In a materials flow supply network, a firm with high out-degree centrality tends to be a common supplier to multiple downstream firms. Such supplier can economize and capitalize on its own internal resources as it aggregates demands from a range of customers (Nobeoka, 1996). Further, this firm is more likely than others to gain access to proprietary assets or information of its customer firms. This firm is in the best position to allocate or channel production or technical information to others in the network (Cassiman and Veugelers, 2002). 3.2.1.2. Closeness centrality in supply network. The calculation of closeness centrality is based on geodesic distance d(ni , nj ) —the minimal length of a path between two nodes ni and nj (Hakimi, 1965; Sabidussi, 1966). In this study, closeness centrality is considered only in contractual relationship networks, as shown in Table 1. In a directed network (e.g., materials flow), the geodesic(s) from ni to nj may not be the same as the one(s) from nj to ni , or there can be two geodesics between two non-adjacent nodes. In the case of supply networks, this does not make physical sense. Therefore, typical node closeness is defined as: ⎡ ⎤−1 g CC (ni ) = ⎣ d(ni , nj )⎦ j=1 where g j=1 d(ni , nj ) is the total distance between ni and all other nodes. At a maximum, the index equals (g − 1)−1 , which happens when the node is adjacent to all other nodes. When all the other nodes are not reachable from the node in question, the index reaches its minimum value of zero. The index can be normalized by multiplying CC (ni ) by g − 1. The value then ranges between 0 and 1 regardless of network size (Beauchamp, 1965). In this study, the normalized index is converted to a 0–100 scale. Nodes with high closeness need not much rely on others for relaying information or initiating communications (Bavelas, 1950; Beauchamp, 1965; Leavitt, 1951). This metric, in a supply network context, thus can represent the extent to which a firm can act autonomously and navigate freely across the network to access resources in a timely manner. Such a firm has comparatively shorter supply chains, both upstream and downstream. Shorter chains translate into less distortion of information and better ability to access reliable information (e.g., demand forecasts, supply disruption) in a timelier manner (Lee et al., 1997; Chen et al., 2000). Such accessibility to high-quality information increases the firm’s capability to match supply and demand (Cachon and Fisher, 2000), resulting in less inventory and lower operational costs (Lee et al., 2000). 3.2.1.3. Betweenness centrality in supply network. Betweenness centrality appears under both types of networks. A firm can lie between a pair of non-adjacent firms either along their materials flow or contractual relationship. The intermediary will have different effects on the firms it links, whether directionally or non-directionally. Measuring betweenness centrality begins with an assumption that a connection between two nodes, nj and nk , follows their geodesics. Therefore, betweenness centrality can be expressed as (Freeman, 1977): CB (ni ) = gjk (ni ) j<k gjk where gjk is the total number of geodesics linking the two nodes, and gjk (ni ) is the number of those geodesics that contain ni . The ni ’s betweenness is then simply the sum of the probabilities that the node lies between other nodes. The betweenness reaches the maximum when ni falls on all geodesics and has a minimum of zero when ni falls on no geodesics. We normalize it to a value between 0 and 100: CB (ni ) = CB (ni ) × 100. [(g − 1)(g − 2)/2] The betweenness can be viewed as indicating how much “gatekeeping” ni does for the other nodes (Borgatti and Everett, 2006; Freeman, 1980; Spencer, 2003). Gatekeeping occurs because a node on geodesic can control the flows of materials or communication (Marsden, 2002). When applying to materials flow networks, firms with high betweenness act as a hub or pivot that transmits materials along the supply chains, and betweenness centrality relates to the extent to which a firm potentially affects the downstream firms’ daily operations (e.g., lead time) and eventually the performance (e.g., final product quality) of the whole network. For instance, if a firm with high betweenness transmits materials to a wrong place or does not respond to changes in demand in a timely manner, it can easily lead to supply disruptions (Chopra and Sodhi, 2004). Similarly, the effects of poor-quality outputs from these firms can easily infect the broader supply network, interfering with normal product flows (Kleindorfer and Saad, 2005). Therefore, operational hiccups caused by such firms can surely hamper the functioning of the entire supply network (Hendricks and Singhal, 2005). Considering the significance of negative impacts such members can have, it would be prudent of the final assembler to ensure high or, at least, consistent operational performance of these firms (Hendricks and Singhal, 2003). In a contractual relationship network, the metric can denote the extent to which a firm can affect the interactions among others in the same supply network. A firm with high betweenness centrality mediates many pathways and thus can either facilitate or interfere with the network communications. The social network literature suggests that a node linking dense regions of relationships enjoys the benefits of non-redundant information to increase its control over others (Burt, 1992, 1998). Supply network research also postulates that a buyer can enjoy the increased sourcing leverage when it lies between two disconnected, competiting suppliers (Choi and Wu, 2009; Wu and Choi, 2005). For instance, the buyer can play two rival suppliers off each other to drive down the purchasing price. 3.2.2. Network-level constructs We now discuss the key network-level metrics. Table 2 summarizes the theoretical interpretation of the metrics and their implications for network performance in the context of supply networks. 3.2.2.1. Supply network centralization. Recall that CD (ni ) is nodelevel degree centrality, and CD (n∗i ) is its maximum value in the network. Then, a general definition for network centralization is (Freeman, 1979): CD = g [C (n∗ ) − CD (ni )] i=1 D . g ∗ max i=1 [CD (n ) − CD (ni )] Given g nodes in the network, the denominator reduces to (g − 1)(g − 2). The value of CD reaches the maximum value of 1 when one node is connected with all other g − 1 nodes, and the others interact only with this node. Its minimum value of 0 occurs when all degree centrality values are equal. In supply networks, centralization can refer to how much power or control the core firms exercise over other network members (Choi and Hong, 2002). In this study, besides centralization based on degree, two other centralization Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 199 Table 2 Network-level metrics and their implications for supply networks. Implication of overall network structurea Network type Network-level metrics Conceptual definition in supply networks Characteristics Performance implications Materials flow Centralization The extent to which particular focal firms control and manage the movement of materials in a supply network Operational authority (e.g., power to make decisions on materials flow) concentrated in few central firms Centralized decision implementation process Complexity The amount of collective operational burden born by the member firms in a supply network More firms engaged in the delivering and receiving of materials More steps required to move the materials along High level of controllability in production planning Low level of operational effectiveness at the network-level (i.e., more time taken to reach a decision and take actions on issues at a local level) Low level of operational efficiency at the network level (i.e., longer lead time from the most upstream to the final assembler or more parts for the same product function) Centralization The extent to which particular focal firms exercise bargaining power or relationship management control over other firms in a supply network Lack of interactions between central and peripheral firms in a supply network Decoupled relationships between firms at different tiers The amount of load on the supply network as a whole that requires relationship coordination More firms involved in transferring information Active interactions at a local level Slow relaying communications from downstream to the final assembler Contractual relationship Complexity a High level of controllability in product design, product quality, and/or cost management Low level of responsiveness to or more time for resolution on issues occurring at a local level Low level of robustness or high degree of vulnerability to supply disruptions (i.e., more time to channel information and a higher likelihood of information distortion across a supply network) Implications given high metric score. indices are also used—ones based on closeness and betweenness centrality. Further, there are other proxy measures of centralization used in this study. They are multiple indices of density that involve the core and periphery sub-groups in a network (see Table 6). When a network is partitioned into two clusters, a core cluster appears among nodes that are densely connected together and a periphery is formed among nodes that are more connected to core members than to each other (Borgatti and Everett, 2000; Luce and Perry, 1949). For instance, in Fig. 1, there are 19 firms in the core group (see Table 6) around Honda and CVT who appear at the center. The rest appears in the periphery. 3.2.2.2. Supply network complexity. Supply network complexity refers to the load on the network as a whole that requires coordination (Choi and Hong, 2002). While the general state of the literature regarding the property of complexity at the network level is still emerging (Butts, 2001a,b; Everett, 1985; Freeman, 1983), we adopt the idea put forth by Kauffman (1993) and Frenken (2000). They propose that network complexity can be indicated by the number of nodes and degree of interdependency among nodes in a given network. Therefore, we use two types of SNA output metrics—sizetype and density-type—to represent the number of supply network members and the level of connectedness among them, respectively. The size-type outputs are shown in network size and core size, and the density-types include network density, core density, periphery density, core-to-periphery (CTP) density, and peripheryto-core (PTC) density. Network size relates to the average path length among nodes in the network (Ebel et al., 2002). More firms in a network translate into more steps and more time needed to complete the same task, whereby creating a higher likelihood of the supply being interrupted en route and higher collective burden born at the system level (Frenken, 2000). Likewise, between the two networks of identical size, more links imply a higher probability that the functioning of the individual nodes in the network is likely to be impeded by others, leading to a greater coordination load on the whole network (Choi and Krause, 2006). For instance, if an OEM has two top-tier suppliers, the firm would necessarily incur a greater amount of coordination load, compared to a situation where there is only one top-tier firm. Therefore, a complex supply networks would be associated with large network size, large core size, high network density, high core density, high periphery density, high CTP density, and high PTC density. Note that in the contractual relation supply networks, the PTC and CTP densities are identical, since every link in the network is non-directional and the adjacency matrix representing this network is symmetric. 4. Research methodology 4.1. Data source Choi and Hong (2002) (hereafter, denoted as C&H) reported three supply networks from raw materials suppliers to a final assembler involved in the production of an automobile center console assembly. The three product lines represented were Honda Accord, Acura CL/TL, and DaimlerChrysler (DCX) Grand Cherokee. Using an inductive case study approach, the authors derived propositions regarding the behavioral characteristics of supply networks. Table 3 provides a review of this particular work. In our analysis, we include all the firms in the supply network as identified in C&H—they are direct suppliers and parts brokers, stretching from raw materials suppliers to the final assembler. As indicated before, each supply network contains two different types of network information—one pertaining to materials flow and another based on contractual relationships. These two different types of network data yield a total of six supply networks—three based on directional materials flow and three based on nondirectional contractual relationships. 4.2. Data analysis The network information from C&H is converted into a binary adjacency matrix (Wasserman and Faust, 1994) that has firms representing both the rows and columns of the matrix. For instance, cell (i,j) would equal “1” if the firms i and j were linked either by materials flow or contractual relationship, and would be “0” otherwise. Supply networks may yield adjacency matrices that are 200 Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 Fig. 1. Materials flow network for Accord. symmetric (i.e., non-directional) or asymmetric (i.e., directional), depending on the nature of the linkages. As noted earlier, a materials flow network is directional and thus asymmetric, while a contractual relationship network is non-directional and thus symmetric. Once generated, the adjacency matrices are imported into UCINET 6 and are used as inputs for network analysis (Borgatti et al., 2002). UCINET is a comprehensive software package for the analysis of social network data. It has been one of the most widely accepted SNA tools for conducting the structural analysis of interorganizational networks (e.g., Gulati, 1995, 1999; Human and Provan, 1997; Rowley et al., 2005; Ahuja et al., 2009). The program contains dozens of network analytic methods such as centrality measures, subgroup identification, role analysis, elementary graph analysis, and permutation-based statistical analysis. While performing SNA, UCINET can create network visualizations. A visualization of each of the six supply networks, also known as a sociogram, is shown in Figs. 1–6. 5. Results 5.1. Node-level results Tables 4 and 5 list key firms in the two types of supply networks. We identify key firms based on their centrality values. Tables 4 and 5 build on Table 1. The supply network constructs shown on the top row come from Table 1, and centrality computations are conducted on the corresponding centrality metrics shown in Table 1. As indicated below each table, there is a cut-off point for each supply network construct (e.g., 10 for in-degree, 6 for out-degree). The cut-off point is determined based on one rule: when there is a noticeable drop-off in the score, the previous score constitutes the threshold. In all cases except one, there are multiple key firms. The exception is out-degree centrality for the materials flow type of DCX’s supply network. Every node in the network, except for the OEM, has only one customer, showing the same value on outdegree centrality; consequently, there was no threshold value. In Tables 4 and 5, the number shown in parenthesis next to a firm name represents the centrality score. 5.2. Network-level results Tables 6–8 show SNA results at the network level. Tables 6 and 7 focus on centralization metrics, respectively, for directional materials flow and non-directional contractual relationships. Table 8 summarizes all complexity metrics for both types of networks. In Table 6, various network-level indicators are shown across three different supply networks. Beginning with network size and density, individual node-level centrality scores are averaged for each supply network. Then, the three network centralization scores are listed. Up to this point, all values reflect network-level attributes. Below the network-level values, Table 6 lists values at the group level. It first shows the size of core group and its density (see Section 3.2.2.1 on supply network centralization for a discussion on core and peripheral groups). It then moves on to listing other group-level measures. Addressing contractual relationship supply networks, Table 7 is constructed much the same way. Since this supply network type is non-directional, network measures shown on the left-side column are slightly different from those of Table 6, as discussed under Table 1. Also note that most of the network-level metrics are in normalized form, which allows us to compare them across the three different supply networks. Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 201 Table 3 Summary of case data from Choi and Hong (2002). Network measures Product type Honda Accord Acura CL/TL DaimlerChrysler (DCX) Grand Cherokee Centralization Two firms, CVT and JFC, are top-tier suppliers to Honda Several second- or third-tier suppliers (e.g., Emhart, Garden State, and Miliken) directly selected by Honda Some third-tier suppliers directly selected by CVT, based on Honda’s core supplier list Honda’s penchant for centralized control when it comes to the product design and supplier selection One top-tier supplier, Intek, a complete integrator of this supply network Honda engaging in directed sourcing at the second, third, and even fourth tiers Intek likewise engages in directed sourcing by selecting its own suppliers and even their supplier’s suppliers, based on Honda’s core supplier list Directed sourcing generally for high-priced or strategic items Honda’s centralized control of the product design activities Textron as the sole top-tier supplier that integrates parts and subassemblies Textron-Farmington and Leon Plastics appear as two key second-tier suppliers Textron assumes the leading role in designing console Directed sourcing occurs only on a limited basis Complexity All together, 50 network entities: 2 first-tier, 21 second-tier, 18 third-tier, 7 fourth-tier, and 2 fifth-tier suppliers Majority of the suppliers at the second-tier level Four different nature of businesses in the network—manufacturing companies, raw materials suppliers (e.g., GE Plastics), distribution centers (e.g., Iwata Bolt), and trading houses (e.g., Honda Trading) Reciprocal relationship between CVT and JFC, two top-tier suppliers, contributing to either reduction or increase of network complexity depending on the relational nature 76 entities in the network: 1 first-tier, 20 second-tier, 28 third-tier, 17 fourth-tier, 9 fifth-tier, and 1 sixth-tier suppliers The coupling between Honda and Intek based on their shared history may reduce the level of complexity The decoupling between Intek and JFC, a second-tier supplier of the critical subassembly, may further the complexity Honda’s effort to centralize second-tier suppliers may increase complexity of the network as a whole 41 entities: 2 first-tier, 10 second-tier, 22 third-tier, and 7 fourth-tier suppliers At the top-tier level, Textron is engaged in assembly work and also acts as a conduit for a part from Leon as it ships the front console mat directly to the DCX plant with Textron’s label No reciprocal relations among suppliers As per DCX’s recommendation, Textron has consolidated the second-tier suppliers, leading to reduced number of second-tier suppliers and subsequently reduced complexity Fig. 2. Materials flow network for Acura. 202 Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 Fig. 3. Materials flow network for Grand Cherokee. Fig. 4. Contractual relationship network for Accord. Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 Fig. 5. Contractual relationship network for Acura. Fig. 6. Contractual relationship network for Grand Cherokee. 203 204 Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 Table 4 List of key firms based on materials flow network. Supply loada d Accord CVT (59 ), JFC (15), HFI (11) Acura Intek (58), Arkay (21), Select Ind. (12) DCX Textron (65), Leon Plastics (31) a b c d Demand loadb Operational criticalityc CVT (15), C&C (7.4), JFC (7.4), GE (7.4), Yamamoru (7.4), Industry Products (7.4) Iwata Bolt (9.1), Tobutsu (6.1), Arkay (6.1), Twist (6.1), Milliken (6.1), Garden State (6.1), Select Ind. (6.1) None CVT (13), Emhart (2), Yamamoru (1.7), Fitzerald (1.7), JFC (1.3) Intek (3), Arkay (1.7) Textron (3.8), Leon Plastics (2.5) Firms with in-degree > 10. Firms with out-degree > 6. Firms with betweenness > 1.0. Centrality score. Table 5 List of key firms based on contractual relationship network. Accord Acura DCX a b c Influential scopea Informational independenceb Relational mediationc CVT (52), Honda (30), Yamamoru (15) Intek (45), Honda (36), Arkay (18), Select Ind. (15) Textron (62), Leon Plastics (35) CVT (57), Honda (53), Yamamoru (40) CVT (79), Honda (64), Emhart (21) Yamamoru (15), Fitzerald (14) Intek (77), Honda (63), Select Ind. (14), Iwata Bolt (12), Arkay (10) Textron (88), Leon Plastics (53) Daimler (15) Intek (62), Honda (56), Arkay (44), Select Ind. (43), Tobutsu (41), HFI (40) Textron (72), Leon Plastics (58) Daimler (46) Firms with degree > 15. Firms with closeness > 40. Firms with betweenness > 10. Table 6 Network-level results for materials flowa supply networks. Network measures 6. Interpretation of results Product type Accord Acura DCX Network size (firms) Network density Average in-degree Average out-degree Average betweenness Centralization (in-degree) Centralization (out-degree) Centralization (betweenness) 28 0.046 4.630 4.630 0.809 0.567 0.106 0.128 34 0.037 3.654 3.654 0.231 0.556 0.056 0.029 27 0.037 3.704 3.704 0.234 0.641 0.001 0.038 Core group size (firms) Core density Core to periphery (CTP) density Periphery to core (PTC) density Periphery density 19 0.067 0.006 0.064 0.000 23 0.059 0.000 0.043 0.000 4 0.250 0.000 0.250 0.000 a Represented by asymmetric matrix. Table 8 re-organizes some information from Tables 6 and 7. It lists values for the select indicators of network complexity—they represent the degree of interdependency among firms. Network size is listed as the first indicator. Network density is then listed in both materials flow and contractual relationships networks. Then, group-level indicators are listed in both types of supply networks. Table 7 Network-level results for contractual relationshipa supply networks. Network measures Product type Accord Acura Network size (firms) Network density Average degree Average closeness Average betweenness Centralization (degree) Centralization (closeness) Centralization (betweenness) 28 0.074 7.407 35.716 7.407 0.479 0.459 0.748 34 0.066 6.595 37.747 5.375 0.413 0.513 0.738 27 0.074 7.407 41.959 5.778 0.585 0.641 0.854 Core group size (firms) Core density CTP or PTC density Periphery density 17 0.125 0.048 0.036 6 0.467 0.179 0.000 3 0.667 0.333 0.000 a Represented by symmetric matrix. DCX In this section, we recapitulate the SNA results shown in Tables 4–8 with reference to the supply network constructs developed in this study (see Tables 1 and 2). We provide network dynamics implications of the node-level results first and then those of the network-level results. A summary of the SNA results at the node- and network-level is shown, respectively, in Tables 9 and 10. 6.1. Node-level implications 6.1.1. Key firms in the materials flow supply networks Table 4 compares groups of firms across supply load, demand load, and operational criticality (see Table 1 for definitions). CVT, a first-tier supplier in Accord supply network, appears highly central, showing the highest scores on all three columns. In other words, CVT assumes the most operational burden on both the supply side and demand side. This firm is tasked with integrating multiple parts into a product, which also means the firm can make the most of its resources by pooling customer demands and the related risks. CVT is also the pivotal player in the movement of materials. Without this firm, the entire supply chain would be disrupted. In contrast, we observe that another top-tier supplier of Accord, JFC, is not as central. Its centrality scores are markedly lower than those of CVT, and there are other second- (i.e., C&C, Emhart, and Yamamoru) and third-tier suppliers (i.e., Fitzerald) who appear more central than JFC. This is because most suppliers supplying to JFC also serve CVT but not the other way around (see Fig. 1). Intek, the top-tier supplier for Acura, appears most central under both supply load and operational criticality. The bulk of network resources flow into and through this firm. However, unlike CVT in Accord network, Intek does not appear central under demand load. This is because the firm primarily receives materials (see Fig. 2). In fact, Iwata Bolt, a second-tier supplier for Acura, comes first under demand load. This simply means that this firm delivers to a relatively large number of buying firms, which implies that this supplier has leverage in allocating its internal resources across multiple customers. Another noteworthy finding is that Arkay, a second-tier supplier, is the only firm that ranks high on all the three centrality metrics. Without conducting SNA, Arkay’s central role in the Acura supply network may very well be overlooked. Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 205 Table 8 Key indicators for network complexity. Network size (firms) Accord Acura DCX 28 34 27 Materials flow network Contractual relationship network Network density Core size Core density CTP density PTC density Network density Core size Core density Periphery density PTC density 0.046 0.037 0.037 19 23 4 0.067 0.059 0.250 0.006 0.000 0.000 17 6 3 0.125 0.467 0.667 0.036 0.000 0.000 0.048 0.179 0.333 There are a comparatively less number of central firms in DCX’s supply network. The implication is that the structure of the DCX network is simpler (see Fig. 3) than those of Honda and Acura. For one, there are no firms listed under demand load. This is because every supplier in this network has only one customer, including Textron and Leon, a top-tier and a key second-tier supplier, respectively. These two suppliers appear under both supply load and operational criticality. Both firms engage in value-adding activities by integrating parts and facilitating their flows. The supply streams in this supply network take place primarily through Textron or Leon. 6.1.2. Key firms in contractual relationship supply networks In Table 5, CVT is again prominent on all centrality metrics in Accord supply network. This firm appears as most influential on the operation of the contractual relationship supply network, just as it does in the materials flow network. Nonetheless, there are a few notable differences. First, Honda does not appear at all in Table 4, but in this network based on contractual relationships, Honda emerges quite visibly (second to CVT) on all three columns. This is because Honda maintains a contractual relationship with many of its second- and third-tier suppliers (see Fig. 4). Second, JFC, a top-tier supplier who appears in all three centrality metrics in Table 4, is gone in Table 5. In other words, when it comes to managing contracts, Honda emerges as central and JFC disappears. Clearly, JFC is more isolated in the contractual relationship network. For Acura supply network, Intek appears yet again as most central, while Honda emerges as central also. Thus, Intek looks like most influential in the contractual relation network and none could bypass Intek to connect with Honda. The network position allows Intek to take control of information and communication flows. One supplier for Acura that appears in Table 5 but did not in Table 4 is HFI. HFI is a lone third-tier supplier that SNA picked up as being a key firm under Informational Independence. This is largely because 0.064 0.043 0.250 0.074 0.066 0.074 HFI does business with other central firms such as Intek and Arkay, and this is how it stays in the loop (see Fig. 5). Unlike Accord and Acura, the list of firms that appear in Table 5 for DCX shows little change. There were two firms (Textron and Leon) in Table 4 and the same firms appear again in Table 5. The only exception is Daimler. Compared to the materials flow network, the OEM is more prominent in the contractual relationship network (Table 5), and this is due to its direct links with two third-tier suppliers, Irwin and E.R. Wagner (see Fig. 6). Daimler thus has leverage over the relationships between these two suppliers and Textron, the top-tier supplier. 6.2. Network-level implications We now turn to discussing the dynamics at the network level. Characterization we make below pertains to the whole supply networks based on Tables 6 and 7. 6.2.1. Characteristics of the materials flow supply networks In Table 6, Accord’s supply network shows a comparatively high density compared to the other two networks of Acura and DCX. Accord’s supply network also features relatively high average scores on the key centrality metrics. Particularly, on average betweenness, Accord’s lead is substantial. It implies that firms in this supply network are more engaged in both delivering and receiving materials than firms in other supply networks. It also means that there are more steps required to move the materials along. From an operational standpoint, it might indicate that this network provides less efficiency (e.g., longer lead time, more parts used for the same function) as it imposes more managerial attention on the firms in a central position. Looking at centralization scores for Accord, indegree score stands out, suggesting the inflow of materials is concentrated in a small group of firms in the supply network. We also note a rather large discrepancy in the scores Table 9 Node-level overview. Materials flow network Contractual relationship network Accord CVT, a 1st-tier suppliers, is most central, and assumes the most operational burden on both supply and demand sides JFC, another 1st-tier supplier, is not as much central as CVT Honda appears not central in this network HFI and C&C, two 2nd-tier suppliers, need to handle high degrees of supply load and demand load, respectively Two 2nd-tier suppliers (Emhart and Yamamoru), and one 3rd-tier (Fitzerald) are also central as a go-between along the materials flow CVT is most central under all three measures—operational flexibility, managerial independence, and relational control Honda emerges as the close second to CVT on all centrality metrics JFC is extinct and becomes isolated in this network Yamamoru, a 2nd-tier suppliers, emerges as central under managerial independence Emhart, a 2nd-tier supplier, is central under relational control Acura Intek, the sole 1st-tier supplier, is most central under both supply load and operational criticality Arkay, a 2nd-tier supplier, is central on every centrality metric Iwata Bolt, a 2nd-tier supplier, is most central under demand load Honda is virtually out of sight in this network Intek is again most central on all three centrality Honda is the close second to Intek on every centrality metric HFI, a 3rd-tier supplier, emerges as key under managerial independence due to its ties with other key suppliers Two 2nd-tier suppliers, Arkay and Select Industries, rank consistently high on all three centrality metrics DCX Textron, the sole 1st-tier supplier, and Leon, a 2nd-tier supplier, are most central under both supply load and operational criticality No central firm under demand load Daimler is rather central only under supply load Little change from materials flow network Textron and Leon are two most central on every centrality metrics Daimler comes next but by a large margin on all three metrics No other firms, than the three firms, appear as central in this network 206 Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 Table 10 Network-level overview. Materials flow network Contractual relationship network Accord Comparatively high overall density Highest average score on all three centrality metrics Relatively high centralization across all three types, and substantial lead on average betweenness score Much higher indegree centralization than the other two types No connectivity among peripheral firms Little reciprocity between the core and peripheral firms (much higher PTC density than CTP density) Peripheral firms engage solely in supplying to core firms Relatively high overall density Highest average betweenness but lowest average on closeness Largest core group with low density Relatively high periphery density Comparatively low PTC density There are more interactions overall among more members Rather complex at the network level Relatively less centralized Acura Comparatively large overall membership but with low density Relatively low average scores on all the three centrality metrics Comparatively low centralization indices Very large core group with very low density Virtually no materials flows among peripheral firms No reciprocity between the core and the periphery firms Network activities concentrated around the core group Comparatively less complex at the network level Largest overall membership but with lowest overall density Lowest average betweenness score More tightly coupled core group No interactions among peripheral firms Network activities mostly concentrated around the core group Relatively high PTC density Comparatively more centralized around the smaller core group Comparatively less complex at the network level DCX Smallest membership with relatively low density Comparatively high indegree centralization, but quite low outdegree centralization Smallest and tightly knit core group No materials flows among peripheral firms Largest discrepancy between PTC and CPT density among three SNs Peripheral firms engage exclusively in supplying to the core firms Relatively more centralized and least complex at the network level Highest average scores on closeness centrality Highest centralization indices Smallest core group with very high density No interactions among peripheral firms By far higher PTC density Majority of network activities centers around the core group Peripheral firms engage only in supplying to the core firms Most centralized and least complex at the network level of CTP density and PTC density, which signifies little reciprocity between the core and peripheral firms. Further, the far-off firms do not interact at all, as demonstrated in the periphery density of 0, and this is true for all product types. In other words, the peripheral firms engage solely in supplying to the core firms. Acura’s supply network has comparatively large membership but low overall density. The three average centrality scores are relatively low. Acura’s supply network, compared to Accord’s, has less number of links and the overall steps required to get things done are not as many, which may indicate higher operational efficiency. Further, based on centralization scores, Acura’s supply network appears as less centralized than Accord’s. At the local level, the core group has very large membership but with relatively low density. Since there are more firms in the core group, it suggests that the power in the network is more spread out; the more flat structure of operational authority again may be an indication that this network works more efficiently (e.g., less time expended to make a decision on issues at a local level). DCX’s supply network has the smallest membership, and the overall density is also relatively low. The centralization index based on in-degree is comparatively high, as is the case with Accord and Acura. However, notable difference occurs with out-degree centralization. It is quite low, indicating that most of the materials flow out to few common dominant firms, and this observation is also supported by the small size of the core group. There is also a huge discrepancy between CTP density and PTC density, which simply means that the majority of materials flow links in the network is concentrated on a small number of firms. As expected, these firms in the core group are tightly knit, as evidenced by a high core density. Such simple structure can provide high operational efficiency at the network-level (e.g., shorter lead time from upstream suppliers to the final assembler); however, if multiple issues were to happen simultaneously they could overwhelm the few central players and could require much more time for resolution. 6.2.2. Characteristics of contractual relationship supply networks The density for Accord is much higher in Table 7 than it was in Table 6. This is because contracts can jump across several tiers. As expected, the same thing happens for Acura and DCX as well. In terms of centrality metrics, Accord’s supply network shows relatively low average closeness but high average betweenness scores. Such a structure may be less responsive or more susceptible to supply disruptions. It would possibly take more time channeling information and there is a higher chance that information becomes distorted on its way along the chains as more firms get involved in transferring it. Therefore, such structure is likely to be less robust or less effective when it comes to coping with supply disruptions. By the same token, the structure would provide greater complexity at the network level for Accord, as also evidenced by Accord’s relatively large core group size (see Table 7). Further, it has relatively high periphery density, which further indicates that the network is complex because there are more interactions going on even among peripheral members. Still, more contacts among members at the local level might facilitate identifying, if any, supply issues occurring locally. Acura’s supply network shows relatively low overall density but with large membership, which correspond with less number of contractual links overall. Regarding average betweenness, this supply network shows the lowest score, indicating that this network needs a smaller number of channels to get things done. Comparatively, therefore, this supply network appears as more efficient, for instance, in managing such issues as supply disruptions because communications at the network level can be comparatively faster and more organized than those of Accord’s, which is also supported by Acura’s comparatively more tightly knit core group and zero periphery density. Interestingly, DCX’s supply network shows the highest average closeness score. In other words, the firms in the DCX’s network are more readily reachable from each other, indicating that information can travel faster across the network. To put it differently, the network structure is more conducive to the centralized control by dominant actors. As might be expected, this supply network features the highest centralization indices among all three supply networks. There is additional evidence for DCX’s high centralization at the network level—the majority of the activities in the supply network seem to center around a very small group of firms (i.e., Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 three core firms) that are highly interwoven together (i.e., the highest core density of 0.667). Further, the firms in the periphery, with no interactions among them, focus on catering to the core firms’ needs, evidenced by high PTC density. Because network information tends to spread relatively fast and converge at a small group of dominant actors, the network as a whole would be comparatively more effective and robust when it comes to dealing with supply disruptions. Particularly, active interactions between core and periphery firms would further enhance such capability of the supply network. 7. Discussion 7.1. Comparisons between SNA results and C&H study 7.1.1. Overlapping and divergent results One of the main findings of C&H was the three OEMs’ varying degrees of centralized control over their supply networks. The SNA results confirm this. In particular, the final assemblers’ practice of directed sourcing is captured in the contractual relationship network structure. For instance, the high values in Honda’s various centralities and overall density in the contractual relationship network, compared to those in the materials flow network, is clearly attributable to the added links that represent Honda’s directed sourcing practice involving its second- and third-tier suppliers. Another finding shared by both studies is the relational salience of those tertiary-level suppliers in the network that are sourced directly by OEMs. All of such suppliers (e.g., Emhart for Accord and Iwata Bolt for Acura) emerge as visible in the contractual relationship network, through their exhibiting high scores on the various centrality metrics or becoming a member of the core group in their respective supply networks. Divergent results between the two studies relate largely to network-level properties such as network centralization and complexity. First, C&H describe Honda’s two supply networks as more centralized than DCX’s. However, SNA suggests the opposite (see Tables 6 and 7). In evaluating network centralization, C&H actually take the perspective of the final assemblers (i.e., Honda and DCX). They present the argument that Honda is more centralized compared to DCX because it has more direct ties with its suppliers (i.e., top-tier as well as second- and third-tier suppliers)—Honda has more centralized control of its supply networks. However, SNA, in contrast, looks at how central all firms are in the supply network, not just the final assembler. SNA evaluates the relative node-level centrality scores of all the network members to arrive at the indicators of network centralization. The two studies also diverge when considering which supply network is most complex. C&H suggest that Acura’s network is most complex. This judgment is based on the network-level physical attributes (e.g., total number of entities, average geographical distance between companies) and qualitative evidence regarding the lack of shared history and the perceived level of decoupling among members. Contrarily, SNA points to Accord’s network as being most complex. This is because SNA focuses on how individual firms and their relationships are connected to one another at the network level. For instance, SNA considers various aspects of interdependence among members in the network, such as network density, core density, periphery density, and PTC density. The two studies, as such, draw different conclusions on some aspects of supply network properties. Nonetheless, we want to caution that this does not mean one is more accurate; rather, we want to say that they just focus on different aspects of the same phenomenon—the case approach focuses on contextual information, whereas SNA operates on numerical breakdown of data on relative positions of members. 207 7.1.2. What C&H offer but SNA does not C&H’s qualitative approach offers a contextually rich picture of network dynamics. For instance, they make statements about the network structure by drawing on such observations as Honda’s strong penchant toward centralized policy with respect to supplier selection and product design and DCX’s practice of delegating authority to the first-tier supplier as to who will be second-tier suppliers and how to design the console. Further, the case method can provide more detailed accounts of how the supply networks operate and behave. For instance, in the Honda’s supply networks, the second-tier suppliers selected directly by Honda tend to be less cooperative with the top-tier supplier, which contributes to furthering complexity at the network level; in the DCX’s network, Daimler commissions the top-tier supplier to consolidate the second-tier suppliers to reduce operational complexity. Such findings are context-specific and would be very difficult for SNA to capture. Also, C&H offer some propositions representing the overarching principles of the supply networks, derived from the qualitative data. For instance, the study observes, “Formalized rules, norms, and policies lead to the varying degrees of centralization in the supply network . . .” (p. 488); “The cost consideration represents the most salient force that shapes the emergence of the supplynetwork structure” (p.488); and “A centralized approach to supply network involves a common list of core suppliers and the design activities are tightly controlled by the final assembler” (p. 489). Only from case-based qualitative studies could such propositions be compiled. SNA would be unable to capture such contextually rich information. 7.1.3. What SNA offers but C&H do not Simply, SNA offers many quantitative metrics that qualitative approaches cannot. By analyzing the structural characteristics of supply networks, SNA brings us new intriguing results that would likely be overlooked by qualitative methods. First, by producing various network metrics, from node- to group- and to networklevel, SNA facilitated a comprehensive analysis of supply networks. For instance, SNA evaluated differing roles of the individual nodes and their relative importance with respect to others in the same network (see Tables 4 and 5). Second, SNA allowed for a comparative analysis of two different network structures—materials flow and contractual relationship. Between the two different network structures, we have observed some divergent results even on the same network metrics (e.g., density, betweenness centrality). Those discrepancies, as noted earlier, come from the fact that the two structures are constructed based on different types of relational connection. Thus, it is not proper to say that one type of link is a more accurate depiction of a given network than the other; but rather the two different types of network information should be considered jointly to fully understand a supply network. Further, SNA enabled a group-level analysis by partitioning each supply network into two structurally distinct clusters—core and periphery sub-groups. The core-periphery analysis in fact facilitated assessing network-level properties across different supply networks (i.e., network centralization and network complexity). 7.2. Academic contributions Our goal in this paper has been to introduce SNA as a means to analyze the structure of supply networks and draw theoretical conclusions from such analysis. Our framework translates key SNA metrics into the context of supply networks, and discusses how roles of individual supply network members vary depending on their relative structural position in the network. Subsequently, we suggested a guideline as to how to identify central nodes and eval- 208 Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 uate them differently. Central firms require possessing a particular set of capabilities corresponding to the roles they assume in the network (see Table 1). For instance, firms with high in-degree centrality should focus on developing a capability in system integration or product architectural innovation (Parker and Anderson, 2002; Violino and Caldwell, 1998); firms with high betweenness centrality may be in a better position to engage in supply risk management. Thus, it would be prudent for a buying company (e.g., OEMs), when selecting or developing a supplier, to consider these issues. We hope that the theoretical framework of this study would be instrumental in facilitating future supply network research adopting SNA approach. The paper’s methodological contribution is two-fold. First, this study demonstrates the value of SNA in studying supply networks. SNA considers all member firms in a given supply network to determine which firms are most important, in what aspect, to the operation of the whole network. Capitalizing on computating power, SNA can generate various analytic outputs reflecting either individual- or group-level behavioral dynamics, which in fact facilitate gaining a more comprehensive and systematic view of network dynamics. Second, applying the widely accepted networklevel analytical concepts (i.e., network density, centralization, and core-periphery), SNA can complement qualitative methods in capturing the structural intricacy of the whole network in a more objective way. As has been demonstrated, SNA has considerable potential for enhancing our studies of supply networks (Borgatti and Li, 2009; Carter et al., 2007) and can effectively complement qualitative methods. 7.3. Managerial contributions Based on C&H’s data, our study brings to the fore the salience of two types of supply networks—materials flow and contractual relationship. We propose that managers consider these two types for any given supply network, as we have demonstrated how the two networks organize and behave differently. For instance, in Acura’s supply networks, the size of the core group becomes much larger when based on materials flow than the contractual relationship (see Tables 6 and 7 for comparison). Also, managers should note that there can be different sets of key firms between the two types of supply network (see Tables 4 and 5). One firm that does not appear as central in one type (e.g., HFI in the Acura network) may be a key player in another. Depending on which type of link to focus on, individual suppliers’ position of importance and the strategic roles will vary. For instance, the key firms in a materials flow network can have a considerable effect on the operational quality of overall supply network, affecting lead time, product quality, OEM’s inventory level, or stockout costs (Bourland et al., 1996). Key suppliers in a contractual relation network could facilitate the timely indentification or resolution of those system-level operational problems and other supply disruption risks (Lee, 2002). Further, it may be prudent for a manufacturing firm to identify central second- or third-tier suppliers using SNA. Some of these suppliers become a key player by being linked to more visible other key firms in the supply network. In other words, some tertiarylevel suppliers emerge as important because they are vital to other more prominent suppliers in supply networks. We anticipate these second- and third-tier suppliers that previously went unnoticed will play a more significant role in future. As the issue of supply chain scalability takes the center stage for safety and sustainability, large final assemblers are moving toward identifying and managing key tertiary-level suppliers. Collecting complete supply network data and applying SNA, as we have done in this paper, may serve as a useful approach. In general, having a pictorial rendition of a supply network will be useful to managers. SNA can help generate network sociograms (see Figs. 1–6). As a visual embodiment of relationship patterns in supply networks, these sociograms can be instrumental in attaining a realistic picture of networking patterns and the dynamics. Just as all graphs, network drawings can help save search efforts, facilitate recognition, and provide interesting new perspectives and insights into supply networks. Also, SNA provides a methodological frame for collecting and organizing data, which will be useful for planning and monitoring changes in the operation of supply networks. The position of a node in the network affects the opportunities and constraints of that node and of others (Gulati et al., 2000; Rowley, 1997). 7.4. Limitations and future directions Our study represents a very first step in theorizing and empirically investigating supply networks using SNA concepts. We acknowledge that our study is limited in ways that suggest opportunities for future research. First, our analysis is confined to a specific automobile module (i.e., center console assembly). Any one supplier in the supply network might be involved in several overlapping supply networks across different product lines. A supplier’s role based on one supply network will look quite different from that derived by considering the multiple supply networks together it is a member of. Therefore, the central roles a supplier plays in our analysis should be qualified to the single product line. It would not be reasonable to consider the results of our analysis as a general statement regarding that supplier. In a similar vein, supply networks are considered basically “egocentric”—centered around a focal actor (Håkansson and Ford, 2002; Mizruchi and Marquis, 2006). The three supply networks studied here were also mapped based on information obtained from the final assemblers. Therefore, any possible effect each supplier’s extended network can have on the firm’s strategic importance to the OEM could not be captured in our analysis. For instance, one second tier supplier to Honda may have a tie to other OEMs. If such extended ties were also counted, certain centrality metrics (e.g., betweenness) for the supplier might have shown different scores from those based on the egocentric network, whereby placing the supplier in a different strategic position with respect to Honda. Such egocentric network approach, albeit considered a reliable substitute for complete (sociocentric) network data (Marsden, 2002), may not be enough to provide a full understanding or potential of a given supplier, embedded within the larger social network (Mizruchi and Marquis, 2006). Third, in quantifying the inter-firm ties, we did not consider the variances in strength. All the links considered in our analysis were treated as having the same weight, while the link an OEM has with the first-tier suppliers should involve more intensive information exchanges (i.e., kanban system) or a greater amount of materials (i.e., larger contract size) than those with the second-tier firms, for instance. Also, we viewed supply networks based on the materials flow and contract connections. However, certainly there are many other relational connection types that can be considered in supply networks, such as ownership, technology dependence, intellectual property, and risk sharing. Network ties could be represented by the number of joint programs or of shared patents, level of trust, or perceived transactional risks. Future studies therefore can incorporate the relative strength of supply ties using SNA as the method can effectively illustrate networks with “weighted” links (Borgatti and Li, 2009; Battini et al., 2007). Exchange ties involving a multi-level interface will have differential impact compared to other comparable supply ties based only on a single type of transaction. We note that most supply networks are considered a scalefree network, whose degree distribution closely follows a power law (Albert and Barabási, 2002; Pathak et al., 2007). That is, most Y. Kim et al. / Journal of Operations Management 29 (2011) 194–211 nodes have very few links and only a small number of nodes (e.g., core firms) have many connections. Future studies may apply the scale-free network metrics to studying supply networks, such as clustering coefficient and characteristic path length. Clustering coefficient measures the degree to which nodes in a network tend to cluster together around a given node (Barabási et al., 2002), and it can inform us of how suppliers behave with respect to the final assembler at both the local and the global level. For instance, it can tell us how suppliers would come together for better coordination, based on some governance mechanism involving an OEM. Indicating the system-level “closeness,” characteristic path length can assist in evaluating whether a given supply network is optimally designed (Braha and Bar-Yam, 2004; Lovejoy and Loch, 2003). Given a supply network, it can be of considerable interest to know how the path length compares to the “best” or “worst” possible configuration for networks with the same number of nodes and lines. This can provide implications for how effectively the network is designed and how robust it can be to possible supply disruptions. Finally, SNA could be applied to advancing existing theories regarding the structure or topology of supply networks. A range of SNA metrics can serve as a useful means in this effort. Such network variables as density and various centralities could be applicable to characterizing typological archetypes of supply network structures, eventually leading to the development of a portfolio of contingent approaches to supply management. In conclusion, we hope that this paper can serve as a call to other operations and supply management researchers regarding the importance of framing supply chains as networks and continuing to develop useful supply network indices. We hope to see more researchers taking advantage of the usefulness of SNA for untangling and understanding the complex phenomena embedded in supply networks. 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MANAGEMENT SCIENCE informs Vol. 52, No. 11, November 2006, pp. 1737–1750 issn 0025-1909 eissn 1526-5501 06 5211 1737 ® doi 10.1287/mnsc.1060.0582 © 2006 INFORMS A Typology of Plants in Global Manufacturing Networks Ann Vereecke, Roland Van Dierdonck Vlerick Leuven Gent Management School, and Faculty of Economics and Business Adminstration, Ghent University, Reep 1, B-9000 Gent, Belgium {[email protected], [email protected]} Arnoud De Meyer Judge Business School, Cambridge University, Trumpington Street, Cambridge CB2 1AG, United Kingdom, [email protected] T he purpose of this paper is to propose a new, empirically derived typology of plants in the international manufacturing network of multinational companies. This typology is based on the knowledge flows between the plants. In our research, network analysis has been used as a methodology for understanding the position of plants in international manufacturing networks. The focus has been primarily on the intangible knowledge network, and secondarily on the physical, logistic network. Our analysis leads to four types of plants with different network roles: the isolated plants, the receivers, the hosting network players, and the active network players. Our analysis shows that the different types of plants play a different strategic role in the company, have a different focus, and differ in age, autonomy, and level of resources and investments. Also, the analysis suggests that the evolution of the plant depends to some extent on the network role of the plant. Finally, two scenarios for the development of a strong network role are identified. The research is useful for the scholar studying the architecture of knowledge networks, as well as for the practitioner who is in charge of an international network of manufacturing units. Key words: manufacturing strategy; knowledge management; international manufacturing; plant networks History: Accepted by William S. Lovejoy, operations and supply chain management; received May 23, 2002. This paper was with the authors 2 years and 1 month for 3 revisions. 1. Introduction The basic question here is how to design and manage the flows of goods, people, technology, and information in international networks (Chakravarty et al. 1997). Our research contributes to this second category of international operations research. Competitiveness today is not solely based on the application of state-of-the-art management techniques in each of the individual plants, but also on the implementation of an integrative strategy on the network of plants (Ferdows 1997a). From a logistics perspective, this requires the optimization of the company’s supply chain. From an organizational perspective, it requires managing the creation and transfer of knowledge in the network. Plants adopt a different role in these networks. As plants differ in product allocation and in focus, they play different roles in the supply chain (Hayes and Schmenner 1978). As they differ in the level of creation, sharing, and absorption of innovations, they play different roles in the intangible knowledge network in the company (Ferdows 1997b). The purpose of our research has been to understand the different roles of plants in this knowledge network. Based on rigorous and in-depth case research, a new typology of plants has been derived. The plant types differ in the extent to which they share inno- In 1964, Skinner warned, “the time has come when we must begin to sharpen the management of international manufacturing operations” (Skinner 1964, p. 126). As competition is globalizing and the complexity of the environment in which companies operate is increasing, managing an integrated international network has become an increasingly important task for manufacturing managers (Bartlett and Ghoshal 1989, Ferdows 1997a). However, despite the importance attached to it by both academics and practitioners, the field of international operations management is still at a relatively early stage of theory development (Roth et al. 1997) and could be enriched by insights from empirical research (Chakravarty et al. 1997). In the field of international operations management, at least two categories of research can be distinguished (Chakravarty et al. 1997). The first category of research consists mainly of international comparisons. The basic question here is to what extent models and concepts in production and operations management are applicable in different countries or regions. The second category studies the management of international networks of facilities, suppliers, and markets. 1737 Vereecke et al.: Typology of Plants in Global Manufacturing Networks 1738 Management Science 52(11), pp. 1737–1750, © 2006 INFORMS vations with the other plants, in the level of visits to and from the other plants, and in the level of communication with the other plants. The analysis also shows that different roles in the knowledge network coincide with different roles in the supply chain. 2. 2.1. Literature Review Operations in a Multinational: A Network Perspective Over the last two decades, research on the structure and organization of multinationals has shifted from a focus on the one-to-one headquarters-subsidiaries relationships toward a focus on managing a network of units (Kogut 1989). Ghoshal and Bartlett (1990, p. 620) claim that the network approach “is particularly suited for the investigation of such differences in internal roles, relations, and tasks of different affiliated units and of how internal co-ordination mechanisms might be differentiated to match the variety of sub-unit contexts.” In the management of these networks, the focus has often been on the flow of information. Doz and Prahalad (1991, p. 160), for example, state that differences in the mission of subsidiaries are reflected in the “pattern and intensity of information flows.” In their more recent work Doz et al. (2001) argue that the success of some multinational companies lays in their ability to “sense” information and knowledge and to distribute it rapidly throughout the network. The information flow is only one type of network relationship between the subsidiaries and headquarters, and among the subsidiaries. The physical flow of components, semifinished goods or end products, financial flows, and “flows” of people moving around in the network are other types of network relationships (Bartlett and Ghoshal 1989). This trend toward describing the multinational company as a network of units can also be observed in the manufacturing strategy literature. Work has been done, for example, in the description of the benefits and methods of the transfer of best practices across the manufacturing network. Chew et al. (1990) show that the improvement of the overall performance of multisite companies depends on the local innovativeness of the plants, as well as on the interplant transfer of these local innovations. Flaherty (1986, 1996) adds to this the importance of coordination. She argues that the coordination of international operations in a network can improve cost and delivery performance and enhance the learning from the experiences of units in the network. However, the systematic analysis of the relationship between the plants in the manufacturing network requires an appropriate methodology. Nohria (1992, p. 8) claims that, “if we are to take a network perspective seriously, it means adopting a different intellectual lens and discipline, gathering different kinds of data, learning new analytical and methodological techniques, and seeking explanations that are quite different from conventional ones.” Network analysis is a particularly powerful methodology for the description and analysis of the structure of networks and the position of the units in the network (Knoke and Kuklinski 1982). The next section describes the network relationships between the units in the manufacturing network from a conceptual perspective. The operationalization of these network relationships and the application of network analysis techniques are described in §3. 2.2. Network Position of Plants The purpose of our research is to understand the position of manufacturing units in international manufacturing networks. Our hypothesis is that distinct plants play different roles in these networks by having relationships of different type and intensity with the other plants and with headquarters. Bartlett and Ghoshal (1989) recognize four types of relationships between subsidiaries: physical goods, information, people, and financial resources. The flow of financial resources in the strict sense of providing capital to subsidiaries is of lesser importance in our study of network relationships between plants, and will therefore not be discussed here. The three other types of relationships—goods, information, and people— differ in their degree of tangibility. Our interest lies primarily in the intangible knowledge network of the multinational, which is explained in the next two sections because we are exploring how the network of production facilities of the multinational may enhance the creation of strategic capabilities. The logistics organization of the multinational, which is reflected in the focus of the plants and in the tangible transfer of components on semifinished goods through the network, is discussed in §4.4. 2.2.1. The Information Network. Two types of information flow can be distinguished: the administrative information flow and the knowledge flow (Gupta and Govindarajan 1991). In a manufacturing context, the administrative information flows consist of information on inventory levels, purchasing requirements, forecasts, production plans, etc. These information flows depend to a large extent on the degree of centralization of manufacturing tasks, such as planning, inventory management, and procurement. From a manufacturing strategy perspective, the knowledge flows are the more interesting ones. It is commonly accepted that one of the main reasons for the existence of multinationals is the possibility to acquire, create, and use technological assets across Vereecke et al.: Typology of Plants in Global Manufacturing Networks 1739 Management Science 52(11), pp. 1737–1750, © 2006 INFORMS national boundaries (Dunning 1993, p. 290). Consequently, the ability to transfer innovations through the multinational’s network is crucial for attaining a competitive advantage. Three categories of innovation flows have been studied: the development and introduction of a new product, the development and introduction of a new production process, and the implementation of a new management system (Ghoshal and Bartlett 1988). 2.2.2. The People Network. The flow of people in the manufacturing network may take different shapes. A typical example is the position of a manager having line or staff responsibility in two or more plants. This can be at the level of the plant manager, as well as the functional levels reporting to the plant manager. This type of relationship can be called “interlocking management” by analogy with the interlocking directorship; i.e., one person being a member of the board of directors of two or more companies (Gerlach 1992). Of equal importance are the “dispatched managers,” i.e., the managers who have been transferred from one operating unit to another, on a permanent or a temporary basis, by analogy with the dispatched director. A third shape of the flow of people refers to the day-to-day operations of the network. These relations between units are realized through “coordinators”—managers traveling frequently between operating units to share information and to accomplish cooperation between the units. The role of such coordinators has received a lot of attention in the organization literature. They are specific examples of what Galbraith (1977) and Mintzberg (1979) have defined as the “liaison devices” of an organization. A major advantage of these coordinators is the opportunity they create for personal contact between people in the organization. Ghoshal et al. (1994) have shown that the relationship among subsidiary managers and the relationship between managers of subsidiaries and managers of headquarters have a significant influence on the frequency of the intersubsidiary communication and on the frequency of communication between the subsidiaries and headquarters. Communication plays an important role as a facilitator of the transfer of innovations in multinationals (Ghoshal and Bartlett 1988, Gupta and Govindarajan 1991). We retain from this short discussion three variables that are particularly relevant for our study: (1) the flow of innovations between the units in the network; (2) the extent to which coordination exists in the network through managers traveling between the units; and (3) the frequency of communication between the units in the network. Interlocking management has not been retained as such in the research because it can be regarded as a special reason for frequent travels between the two plants involved. Dispatching has not been retained either because we assume that this creates a tight relationship between the dispatching and the receiving unit only if the dispatched manager keeps in touch with his original unit. Measuring the communication between the two units then captures this. 3. Research Methodology 3.1. Case Research The research reported here is part of a larger research study on the international plant configuration. The research was exploratory, i.e., we wanted to understand the “how” and “why” of the international plant network. Thus, case study research has been preferred over other research methodologies (Yin 1984). To achieve precision and rigor, we followed the methodological guidelines proposed by Eisenhardt (1989), Miles (1994), and Yin (1984). Without being exhaustive, we mention that a strict research protocol has been designed, a questionnaire with both closedand open-ended questions has been developed as guidance for the interviews, accommodations have been made to avoid interview fatigue, and both qualitative and quantitative data have been collected in a rigorous and structured way and have been analyzed in a systematic way. Several variables have been measured through multiple item measures. The reliability of these variables has been assessed by calculating the Cronbach alpha, and factor analysis has been used to reject or confirm the assumption that some theoretical constructs underlie the items (Carmines and Zeller 1979, DeVellis 1991). To enhance construct validity, multiple raters have been used. This tactic avoids the risk that data comes from a single respondent with a biased view or with limited access to information (Speier and Swink 1995, Boyer and Verma 1996). The intraclass correlation (ICC) method has been used to assess the interrater reliability of the variables. The ICC index measures the variance of the scores of the raters within a plant, relative to the between-plant variance. Data on the ICC for all variables used in the analyses can be found in Appendix 1. 3.2. Data Collection The case research has been carried out in eight manufacturing companies headquartered in Europe, in different industries: food products (two companies), textile goods, plastic products, leather products, primary metal, fabricated metal, and electrical goods. Thus, no single industry dominates the sample. The companies had between four and 10 manufacturing plants. The primary selection criterion for the cases has been diversity, at the level of the company as well as the plant. At the company level, it is important to have diversity in terms of the international 1740 environment in which the company operates because one of the research objectives was to explore the link between the characteristics of the company’s international environment and the plant configuration in the company. Consequently, the cases are distributed over the integration/responsiveness grid, as defined by Bartlett and Ghoshal (1989). Two of the cases are classified as “global,” two as “transnational,” and four as “multinational” (Vereecke and Van Dierdonck 1999c). Diversity at the plant level has been obtained by selecting companies with a minimum of four plants, spread over a broad geographical region—the rationale being that with three plants or less, companies have few opportunities for differentiating the role and focus of their plants. A geographical spread of the plants (pan-European or even global) was expected to result in a broad range of drivers for establishing the plant, and therefore also in a broad range of plant roles (Ferdows 1997b). The sample was limited to companies with their headquarters in Western Europe. Data have been gathered at two levels of analysis: the plant and the company. • Interviews have been conducted with the general manager and with manufacturing managers at headquarters. In total, data has been collected on 59 manufacturing plants, through 37 interviews (with a total duration of approximately 120 hours). The number of interviews varied between two and six per case. A structured questionnaire with closed- and openended questions has been used as a guide through the interviews. • A second questionnaire has been sent to the plant managers and/or the manufacturing managers in the distinct production plants. One hundred fourty four questionnaires have been sent to 54 out of the 59 plants. For five of the plants, headquarters asked us not to send a questionnaire to the plant managers. Eighty three percent of the questionnaires have been returned from 50 plants. This implies that in total we have received data from the plant managers on 50 out of the 59 plants (85%). The number of questionnaires returned from the plants varied between one and five per plant. • Information has also been obtained from desk research on company brochures, publications, and company archives. Fourty-two plants were located in Europe, spread over 14 different countries. The other 17 plants were spread over 10 different countries in East Asia and the Middle East, the United States and Canada, and South Africa and Australia. We thus have a truly international sample. The number of years the plant had been part of the company ranges between 0 (this plant was starting up at the moment of the research) Vereecke et al.: Typology of Plants in Global Manufacturing Networks Management Science 52(11), pp. 1737–1750, © 2006 INFORMS and 50 years, with an average of 17 years. The number of employees in the plants ranges between 77 and 1,100 with an average of 340. 3.3. Operationalization of the Network Position of the Plants In describing the manufacturing network of a multinational company as an information and people network, the network units considered are all the plants and the group of managers in headquarters responsible for manufacturing (in this paper, referred to as “headquarters”). As discussed earlier, the network relationships considered in this research are the flows of innovation, the use of coordinators, and the communication between the units in the network. The innovation transfers have been measured by asking managers in the plants (through the mail questionnaires) and in headquarters (through the interviews) to enumerate and describe the transfers of product, process, and managerial innovations they know of over the past three years. A similar operationalization has been used by Ghoshal and Bartlett (1988). The information that has been gathered from these different sources has been checked, complemented, and corrected by at least one manager in headquarters, in the course of the in-depth interviews. The presence of coordinators has been operationalized as the extent to which people are traveling from one unit to another. This information on people flows has been collected through the mail questionnaire to the plants. The measurement is based on the tool used in the research by Ghoshal (1986). The respondents had to report the number of days they had spent, over the previous year, in headquarters and in each of the plants in the company’s network. One of the questionnaire items measures the communication between the managers in the plants and in headquarters. However, such self-reported answers may suffer from recollection problems. This problem is severe if the data collection method consists of an interview or questionnaire asking the respondent to name the persons he/she communicates with frequently. This approach has been used in early studies of communication networks in R&D laboratories (Allen 1977). An alternative approach is to provide a list of people, and to ask the respondent with whom on this list he/she has communicated, rather than letting the respondent name the people he communicated with (Knoke and Kuklinski 1982). This approach has been followed in our research. A score of 3, 2, and 1 has been given to daily, weekly, and monthly communication, respectively. Bartlett and Ghoshal (1989) have also preferred this scoring system. The primary network measure used in our research is the centrality of the plant in the network. If network relations are mutual (as is the case for the communication network), we measure centrality of the Vereecke et al.: Typology of Plants in Global Manufacturing Networks 1741 Management Science 52(11), pp. 1737–1750, © 2006 INFORMS unit through its degree. The degree of a unit is defined as the proportion of other units with which a unit has a direct relationship (Knoke and Kuklinski 1982). If network relations are not mutual (as is the case for the flows of people and innovations), two degree measures are used: the unit’s indegree and outdegree (Knoke and Kuklinski 1982). The indegree of a unit is defined as the proportion of relations received by the unit from all other units. The outdegree of a unit is defined as the proportion of relations from that unit to all other units. Based on these definitions of centrality, the following network variables have been defined: • The communication centrality of plant i captures the frequency of communication of the manufacturing staff of plant i with the manufacturing staff of the other units in the network. • The innovation indegree of plant i captures the intensity of the innovation flow transferred (and implemented) from the other units to plant i. • The innovation outdegree captures the intensity of the innovation flow transferred (and implemented) from plant i to the other units. • The people indegree of the plant captures the number of days plant i has received visitors from the manufacturing staff team of the other plants. • The people outdegree of plant i captures the number of days manufacturing staff people of plant i have been visiting other plants in the plant configuration In network analysis, the consequences of missing data are severe because the lack of data from a single unit implies the lack of data on the N − 1 possible relationships of this unit with the other units in the network. Estimates such as centrality can therefore be distorted if data are missing. Consequently, great care has been taken so as to maximize the response rate (Vereecke and Van Dierdonck 1999b). As suggested by Ketchen and Shook (1996), the number of clusters has been determined through the use of multiple techniques. • Upon visual inspection of the dendogram, we recognize a structure with four clusters. • A four-cluster classification accounts for 56% of the variance in the data. Disaggregation into five, six, and seven clusters adds approximately 6% to the variance explained at each step. After seven clusters, the increases in R2 are low (below 3%). This observation points at a classification into four or seven clusters. • The cubic clustering criterion (CCC) points at nine clusters. However, tests have indicated that the CCC may suggest too many clusters (Milligan and Cooper 1985). • We have used the analytics software SAS to perform a number of the tests that have been put forward by Milligan and Cooper as most effective (Milligan 1996). The pseudo F statistic, developed by Calinski and Harabasz (1974), has local peaks at two and seven clusters. The pseudo t 2 statistic, based on Duda and Hart (1973), indicates a clustering of the data in two, four, or seven clusters. We conclude that the different test routines point at a clustering into two, four, or seven clusters. Because there is partial agreement among the test results, Milligan (1996) suggests opting for the larger number, that is, seven. However, when going from the four to the seven-cluster solution, we see that the pattern of three clusters is roughly maintained, while the fourth cluster falls into four smaller clusters (including a cluster of one unit), which are difficult to distinguish. Consequently, the seven-cluster solution merely adds complexity without providing revealing insights. We have therefore opted for a classification into four clusters. 3.4. Clustering of the Data To ensure the validity of the network typology, a twostage procedure has been followed to cluster the data (Ketchen and Shook 1996). We had sufficient data on 49 of the plants to involve them in the cluster analysis. Ward’s hierarchical clustering method has been used to define the number of clusters. This number of clusters has then been used as the parameter in the nonhierarchical K-means clustering method with Euclidian distance measure. K-means clustering is preferred over the hierarchical cluster methods for the development of the typology because it is an iterative partitioning method and thus is compensating for a poor initial partitioning of the cases. Because the units of measurement for the network relationships differ substantially and Euclidian distance is used as the distance measure in the cluster analysis, the variables have been standardized prior to the clustering (Aldenderfer and Blashfield 1984, p. 21). 4. Empirical Results 4.1. A Network Typology of Plants The four clusters represent different positions of plants in the plant network of information and people. The average of the network variables in each of the clusters is represented graphically in Figure 1. The typology of plants resulting from this cluster analysis is summarized in Table 1. We distinguish three levels for each of the variables: “low” for average value below 0; “medium” for average level between 0 and 1; and “high” for average value above 1. These cut-off values are defined on the standardized variables. Plants in Cluster A occupy an “isolated” position in the plant network. Few innovations reach the plant, few innovations are transferred to other units, few manufacturing staff people come to visit such a plant, few manufacturing staff people from this plant go Vereecke et al.: Typology of Plants in Global Manufacturing Networks 1742 Figure 1 Management Science 52(11), pp. 1737–1750, © 2006 INFORMS Whereas in type C plants the inflow of visitors is significantly higher than the outflow p < 1%, in type D plants the outflow is higher than the inflow p < 5%. The D plant is thus highly involved in the network, and takes a more active role than the C plant. We label them as the “active network players.” Network Clusters: Graphical Representation Plot of means for each cluster 3 2 1 0 –1 Cluster D Cluster C Cluster B Cluster A –2 Communication centra Innovation outdegree Innovation indegree People indegree People outdegree Variables visit other plants, and there is little communication between the manufacturing staff people of this plant and the other manufacturing managers in the network. A plant in Cluster B is comparable to the isolated plant on all but one variable: it receives more innovations from the other units in the network. We will therefore label these plants as “receivers.” Clusters A and B thus consist of plants that are only weakly embedded in the manufacturing network. They represent 37 out of the 49 plants in the sample. Clusters C and D consist of plants that are true network players. A type C plant frequently exchanges innovations, both ways, with the other units and its manufacturing staff communicates extensively with the other manufacturing managers in the network. A C plant is also frequently hosting visitors from other units in the network. In the network, the C plant thus takes the role of the “hosting network player.” The type D plants differ from the type C plants in two aspects: First, the level of communication centrality and the outflow of innovations are even higher in the type D than in the type C plants (significantly different at p = 10% for communication centrality and at p = 5% for innovation outflow). Second, the major flow of visitors is in the opposite direction. Table 1 Network Typology of Plants Network variable Number of plants in cluster Communication centrality Innovation indegree Innovation outdegree People indegree People outdegree Cluster A Isolated Cluster B Receiver Cluster C Hosting network player 11 Low Low Low Low Low 26 Low Medium Low Low Low 8 Medium Medium Medium High Medium Cluster D Active network player 4 High High High Medium High 4.2. Cluster Validation Analysis of variance on the variables used to generate the cluster solution is frequently used to test the validity of the cluster analysis solution. The test results are summarized in Table 2. However, we do not want to overemphasize the value of this analysis of variance. Because the clustering method attempts to minimize variance within the clusters, it is logical that the F -test is significant (Aldenderfer and Blashfield 1984, p. 65). External criteria analysis is more appropriate. Such analysis is based on statistical tests on variables that have not been used to generate the cluster solution, and yet are relevant (Aldenderfer and Blashfield 1984, Milligan and Cooper 1985). A variable that is strongly related to the typology discussed here is the concept of the “strategic role” of the plant. Building on the work done by Ferdows (1989), we define the importance of the strategic role of the plant as the extent to which the plant contributes to the other units in the manufacturing network (Vereecke and Van Dierdonck 1999a). We have measured the importance of the strategic role of the plant on a nine-point Likert scale, describing plants which have as their main goal “to get the products produced” at the lowest extreme, to plants that are a “center of excellence, and serve as a partner of headquarters in building strategic capabilities in the manufacturing function” at the highest extreme. Given our definition, the importance of the strategic role of the plants in Cluster D should be high. The importance of the strategic role of the plants in Clusters A and B, on the other hand, should be low because these plants make little contributions to the plant network. The plants in Cluster C are expected to play a strategic role of medium importance. The average and median of the importance of strategic roles are shown in Table 3. We should note here that for the importance of the strategic role, as Table 2 Analysis of Variance on Four-Means Cluster Solution Network variable Communication centrality Innovation indegree Innovation outdegree People indegree People outdegree F p-level 12, 18 17, 38 21, 69 47, 81 14, 76 0.000006 0.000000 0.000000 0.000000 0.000001 Vereecke et al.: Typology of Plants in Global Manufacturing Networks Management Science 52(11), pp. 1737–1750, © 2006 INFORMS Table 3 Cluster A Cluster B Cluster C Cluster D Overall Importance of Strategic Role of the Plants Valid N Mean Median 11 26 8 4 49 4.80 4.52 5.76 7.97 5.07 4.67 4.69 6.44 8.10 4.80 Median test: obs-exp below median∗ 039 173 −008 −204 ∗ Number of cases observed minus number of cases expected below the overall median level of strategic role, that is, below 4.80. A positive number shows the number of cases observed below the overall median, and consequently indicates a relatively low level of strategic role in the cluster. well as for most of the plant characteristics that will be discussed later, the assumption of normality is violated. For those variables, the nonparametric alternatives to the ANOVA, the Kruskall-Wallis and Median Tests, have been used. The Kruskal-Wallis test indicates a significant difference in the level of the strategic role between the clusters p < 10%. The Median Test confirms that the difference in strategic role follows the hypothesized pattern, as can be seen in Table 3. Cluster B contains slightly more cases below the median level of strategic role than could be expected if the strategic role were evenly distributed over the four clusters, indicating a relatively low level of strategic role. Cluster D contains more cases above the median level of strategic role than could be expected if the strategic role were evenly distributed over the four clusters, indicating a relatively high level of strategic role. The MannWhitney U-Test confirms that the level of strategic role in Clusters A and B is significantly lower p < 5% than in Cluster D. 4.3. Future Strategic Role of the Plant We have discussed the relationship between the network position of the plant and the importance of the strategic role played by the plant. Our research also provides information on the expected changes in the strategic role of the plant. The interviewees were asked to estimate the importance of the strategic role of the plant as they expect it to be in five years on the nine-point Likert scale described above. The data suggests that in Clusters C and D, only a few marginal increases and decreases in strategic role are expected. This suggests that the plants which occupy an integrated position in the network (Clusters C and D) are fairly stable in terms of the importance of the strategic role they play in the company. Several of the A and B plants, on the other hand, are expected to experience an increase in strategic role. For some, the expected increase is quite substantial. Given the relationship that we observed between the role of the plant and its network position, it is fair to expect that these plants will probably be moving from Clusters A or B toward 1743 Clusters C or D. Several of the other plants in Clusters A and B are expected to experience a decrease in strategic role. Again, for some, the expected decrease is quite substantial. It is clear that these two clusters of nonintegrated plants are less stable than the two clusters of integrated plants. An example illustrates our point. Two of the “receiver” plants in the sample have been closed since we started the case research. We do not want to infer here that the plants in the “isolated” or “receiver” clusters are on the waiting list for closure. The examples of plants with a positive expectation in strategic role would certainly contradict this point. Our hypothesis is that the plants in these two clusters are in a variable position, and that this variability may lead toward an increase as well as a decrease in terms of the importance of the role the plant plays in tomorrow’s network. These plants seem to provide strategic flexibility in the network. It is interesting to mention that the decrease in strategic role that is predicted by headquarters for some of the isolated plants and the receivers is not expected by the managers in the plants. The lack of network relationships for the isolated plants and the receivers seems to create a gap between the expectations of plant management and the considerations in headquarters. It may also suggest that the managers in A and B plants are less involved in strategic decision making and, thus, are less well informed. 4.4. Characteristics of the Plant Types To better understand the network typology of plants, the four types of plants have been compared on a set of plant characteristics. We have analyzed: • The age of the plant (number of years the plant has been part of the company). • The size of the plant (expressed in number of employees). • The focus of the plant (Hayes and Schmenner 1978, Collins et al. 1989): Product focus: the extent to which the plant focuses on a narrow portion of the company’s product range, and Market focus: the extent to which the plant focuses on a narrow portion of the geographical market served by the company. • The supplier/user relationship with other plants in the network: the extent to which a plant supplies components or semifinished goods to or uses components or semifinished goods from another plant in the network. It has been measured as the centrality (outdegree and indegree) of the plant in the physical network of goods. The outdegree of plant i captures the portion of plants in the plant configuration, to which plant i supplies components or semifinished goods. The indegree of plant i, (analogously) captures 1744 the portion of plants in the plant configuration, from which plant i receives components or semifinished goods. • The level of investment: A list of 14 potential investments has been included in the questionnaires. From this list of 14 items, four types of investment have been identified through factor analysis: (1) Investments in the production process, that is, in setup time reduction, plant automation, process analysis, productivity improvement, and throughput time reduction (Cronbach alpha of the resulting factor = 077). (2) Investments in planning, that is, in material and/or capacity planning and just-in-time systems (Cronbach alpha of the resulting factor = 079). (3) Investments in managerial improvement programs, that is, in statistical process control, supplier partnerships, total quality management, and employee participation programs (Cronbach alpha of the resulting factor = 073). (4) Investments in new product development. • The autonomy of the plant. Both strategic autonomy and operational autonomy have been measured through questionnaires administered in the plants. A similar approach has been followed by Ghoshal (1986), Bartlett and Ghoshal (1989), and De Bodinat (1980). Two dimensions of strategic autonomy have been identified, through factor analysis: (1) Strategic autonomy in decisions concerning the operations of the plant, that is, the decision to develop a new product or to introduce a new planning system and the selection of a new supplier (Cronbach alpha of the resulting factor = 081). (2) Strategic autonomy in decisions concerning the design of the plant, that is, the decision to develop a new production process and the choice of a new technology (Cronbach alpha of the resulting factor = 085). Two dimensions of operational autonomy have been identified, through factor analysis: (1) Operational logistics autonomy, that is, in developing a production plan, placing purchasing orders, managing inventories (Cronbach alpha of the resulting factor = 084). (2) Operational autonomy in design and engineering, that is, in developing new products and processes (Cronbach alpha of the resulting factor = 088). • The level of capabilities in the plant. Two types of capabilities are distinguished: the capabilities to develop new products and managerial capabilities. They have been measured in the headquarters interviews through a 1–9 Likert scale. The Cronbach alpha for this construct was 0.85. • The performance of the plant. Performance has been measured relative to the target set for the plant. Performance data has been obtained from a list of Vereecke et al.: Typology of Plants in Global Manufacturing Networks Management Science 52(11), pp. 1737–1750, © 2006 INFORMS nine performance items, included in the questionnaire sent to the plant management teams. Because this performance data is self-reported, it is important to have data from multiple respondents per plant, and to evaluate the interrater reliability. Two dimensions of performance have been identified through factor analysis (see Appendix 1): (1) Performance on time measures, that is, performance relative to the target set for manufacturing throughput time, delivery lead time, and on-time delivery to customers (Cronbach alpha of the resulting factor = 085). (2) Performance on cost and quality measures, that is, performance relative to the target set for unit production cost, productivity of direct workers, defect rates, and overall product quality (Cronbach alpha of the resulting factor = 083). The results of the (mostly nonparametric) comparisons of the four clusters on these variables are listed in Table 4. For those variables that showed a significant difference across the four clusters (with significance level p < 10%), pairwise comparison of the mean or median is reported in Table 4. We conclude from these comparisons that (1) Plants in Cluster C are significantly older than plants in Clusters A and B. (2) Plants in Cluster A are significantly more market focused than plants in Clusters C and D; and plants in Cluster B are significantly more market focused than plants in Cluster C. (3) The outflow of components and semifinished goods is significantly lower for plants in Clusters A and B than for plants in Cluster D. (4) The inflow of components and semifinished goods is significantly lower for plants in Cluster A than for plants in Cluster B; and is significantly lower for plants in Cluster B than for plants in Clusters C and D. (5) The level of strategic autonomy in plant design for plants in Cluster A is significantly lower than for plants in Clusters B, C, and D. Plants in Cluster B have a significantly lower level of strategic autonomy in plant design than plants in Cluster D. (6) The level of process investment in plants in Cluster D is significantly higher than in plants in Clusters A, B, and C. (7) Plants in Cluster A invest significantly more in managerial improvement programs than plants in Clusters B and C . (8) The level of capabilities in plants in Cluster B is significantly lower than in plants in Clusters A, C, and D. Table 5 summarizes the characteristics of the clusters that result from these comparisons. The comments made throughout the interviews provide some additional insights in the profile of the clusters. These comments are listed in Appendix 2. Vereecke et al.: Typology of Plants in Global Manufacturing Networks 1745 Management Science 52(11), pp. 1737–1750, © 2006 INFORMS Table 4 Statistics on Plant Characteristics by Cluster Mean/median Plant characteristic Variable A B C D Difference between clusters Age Number of years plant is part of company 111 168 306 197 Anova p < 1% A < Bns /A < C∗∗ /A < Dns /B < C∗∗ /B < Dns /C > Dns Size Number of employees Number of workers Number of salaried workers Number of manufacturing staff people 154 111 43 13 240 165 43 21 362 251 126 41 533 308 226 40 Not significant Not significant Not significant Not significant Market focus Proportion of market range supplied by the plant 0 18 0 63 0 90 0 89 Kruskal-Wallis Anova with p < 5% Mann Whitney U-test A < Bns /A < C∗∗ /A < D† /B < C∗ /B < Dns /C ≈ Dns Product focus Proportion of product range 0 15 0 22 0 30 0 38 Not significant Supplier/user relationship Outdegree 0 0 0 0 47 Kruskal-Wallis Anova with p < 5% Mann Whitney U-test A ≈ B/A ≈ C/A < D∗∗ /B ≈ C/B < D† /C < Dns Indegree 0 0 11 0 22 0 42 Kruskal-Wallis Anova with p < 5% Mann Whitney U-test A < B† /A < C∗∗ /A < D∗ /B < C∗ /B < D† /C < Dns Operational autonomy Logistics Development and engineering 62 44 69 48 64 58 58 62 Not significant Not significant Strategic autonomy Operations of the plant Design of the plant 41 37 52 48 51 57 54 63 Not significant Anova p < 5% A < B∗ /A < C∗∗ /A < D∗∗ /B < Cns /B < D† /C < Dns Investment Process investment 55 53 51 68 Investment in planning Managerial investment 44 65 49 49 46 49 63 57 Anova p < 10% A > Bns /A > Cns /A < D† /B > Cns /B < D∗ /C < D∗ Not significant Anova p < 5% A > B∗∗ /A > C∗ /A > Dns /B ≈ C/B < Dns /C < Dns Not significant New product investment 49 52 57 70 Plant capabilities Level of resources 64 53 64 75 Anova p < 5% A > B† /A ≈ C/A < Dns /B < C† /B < D∗∗ /C < Dns Performance relative to target Time performance Cost and quality performance 10 10 072 0 63 084 0 02 082 0 69 Not significant Not significant Notes. Variables for which the assumption of normality is rejected are in italic. For those variables, the median value is mentioned (in italic). For the other variables, the mean value is mentioned. ∗∗ Significant at p < 1%; ∗ significant at p < 5%; † significant at p < 10%; n.s.—not significant at p < 10%. 5. Discussion Some general lessons can be drawn from the plant typology and the characteristics of the four types of plants. First, the plants providing innovations to the manufacturing network, the “hosting network players” and the “active network players,” are at the same time receivers of innovations from other units in the network. Apparently, transferring knowledge is beneficial, not only for the receiver, but also for the provider. An explanation may be that the quality of the relationship between two units is a major factor in the exchange of innovations, or as Szulanski (1996, p. 36) has put it, “the relationship serves as a conduit for knowl- edge.” Once such a relationship has been established, it works in both directions. Second, the analyses show that there is a strong link between the position of the plant in the intangible network of ideas and in the tangible network of goods. This is in line with Nonaka and Takeuchi (1995), who argue that codified and noncodified knowledge complement and reinforce each other. The “isolated” plant, which is not actively taking part in the network of ideas, is also isolated in the physical sense: we observed very little flows of components or semifinished goods from these plants to the other plants in the network, and vice versa. The network players (type C and D), on the other hand, are typically sup- Vereecke et al.: Typology of Plants in Global Manufacturing Networks 1746 Table 5 Management Science 52(11), pp. 1737–1750, © 2006 INFORMS Summary of Plant Characteristics by Cluster Plant characteristics A Relatively young; market focused; little inflow and outflow of components and semifinished goods; relatively low level of strategic autonomy in plant design; relatively high level of managerial investment B Relatively young; little outflow of components and semifinished goods; relatively low level of managerial investment; relatively low level of capabilities C Relatively old; broad market; high inflow of components and semifinished goods; relatively low level of managerial investment D High inflow and outflow of components and semifinished goods; relatively high level of strategic autonomy in plant design; relatively high level of process investment pliers to the other plants (in the case of Cluster D) or customers of the other plants (in the case of Cluster C) for components or semifinished goods. Kobrin (1991, p. 19) argued that “the two most important intrafirm flows are products and technology, and the latter is often embodied in the former,” and also observed this link between knowledge and physical flows. Our research suggests that the product is not only a carrier of technological product and process innovation, but also of managerial innovations. Third, we see that building network relations takes time. The average age of the networked plants (type C and D) is 28 years, whereas the average age of the two more isolated types of plants (type A and B) is only 15 years. The difference in age between these two groups is significant p < 1%. Networks apparently develop over a long period of time. A fourth conclusion is that the four different network roles reflect very different plant characteristics. The “isolated” plant in Cluster A is very independent. In its isolated position, it does not contribute to the network, but on the other hand, it also does not depend on the other network units for its components or for maintaining or improving its manufacturing capabilities. Plant management has the capabilities to run the plant independently. The receivers in Cluster B typically are local players that need support— technical and/or managerial—of headquarters or the other plants in the network for their survival. They need this support either because of the negative attitude and lack of skills in the plant, or because of the strategic decision of headquarters to keep investments in the plant relatively low. The hosting network players (Cluster C) are typically fairly old, they supply a broad market, and they are characterized by a low level of managerial investment. The hosting network player has been observed in seven of the eight companies studied. With one exception, this role is played by only one of the plants per company. It is interest- ing that half of the eight C plants are the “mother plant,” the earliest plant in the network, located close to headquarters. We hypothesize that because of its age, the broad market it supplies, and its easy access to headquarters, the plant has gained a lot of experience, which explains why the plant is seen as a competence center by other plants. The other four C plants are located close to another plant with which they have established tight relationships. The inflow of people in these C plants dominantly comes from this neighboring plant, which also has a higher level of strategic role. In two cases, the neighboring plant happens to be a D plant. The profile we see here is one of a satellite plant that is heavily influenced by the presence of another network unit. We conclude that the scenario which leads to a C-type plant seems to build on heritage: the network relationships exist because the plant has been in the network for a very long time and is located close to headquarters or to an active network player. The C plant seems to undergo this scenario in a passive way, rather than to play an active role in it. The scenario that emerges from the characteristics of the type-D plants is more dynamic and active. These plants build capabilities through investments under a relatively high level of autonomy. Such plants are actively building network relationships by sending manufacturing staff to other plants and through extensive communication. It is their enthusiasm and their technical specialization that makes them an important network player. From interaction with managers about the typology, we have noticed that the D cluster is an intriguing category for plant managers. The D plants are typically plants that act as a center of excellence or as a pilot plant for new products, they are regarded as the “think tank” or “engine” in the network, and are known as the technical “specialist” plant in the network (see Appendix 2). This intriguing profile raises questions as to the further evolution of these plants, which makes it an issue for future research. Fifth, there is no significant difference in performance between the clusters. Reaching the targets on cost, quality, or time measures does not appear more or less difficult in the distinct clusters. This suggests that there is not a unique optimal network position for a plant. Rather, the network position of the plant should be regarded from a contingency perspective. Finally, the analyses suggest that the future perspectives of the plant depend on the plant’s network position. Plants that are strongly embedded in the production network are expected to maintain the high level of strategic role they are already playing in the network. The future of plants in rather isolated positions has been predicted to be in two opposite directions: some plants are expected to grow Vereecke et al.: Typology of Plants in Global Manufacturing Networks 1747 Management Science 52(11), pp. 1737–1750, © 2006 INFORMS in strategic importance and are assumed to develop network relationships; others are expected to become less important and may even disappear from the manufacturing network. A possible explanation may be that in case of overcapacity and cost cutting, an “isolated” or “receiver” plant is a welcome candidate for disinvestment or closure. Closing such a plant implies a reduction of overall capacity, which is exactly what is aimed at. It does not imply, however, an important reduction in knowledge transfers because these plants do not contribute considerably to the other plants in the network. This is apparently a headquarters’ decision plant managers are not aware of. 6. Contributions to Researchers and Practitioners Previous classifications of plants have focused on the tangible characteristics of plants: the products the plant produces, the processes it has in place, the markets it serves, and the parts it supplies to other plants in the network (Hayes and Schmenner 1978). The typology developed in our research differs, as it classifies plants on the basis of their position in the intangible knowledge network. We focus primarily on flows of knowledge, rather than flows of goods. The conclusions of our work are therefore useful to any scholar who wants to study the architecture of knowledge networks in manufacturing, and eventually in other environments such as R&D or service operations. The research has allowed us to identify, among the plants we studied, 12 network players, i.e., plants that showed a strong interaction with other units in the network. This interaction between plants is a fairly new trend, or at least, a trend not previously well documented. Moreover, our research offers a methodology for identifying network relationships in manufacturing networks. To the manager in charge of a multinational network of manufacturing plants, the typology serves as a “toolbox” for drawing a map of the plant network. In our multiple discussions with managers about the typology, we learned that the typology has high face validity to them, and allows them to classify their plants, even without actually measuring the in- and out-flows of the plants. An evaluation of this map may help them in identifying possible gaps or unbalances. Because the position of the plant in the network does not impact the plant’s performance, any of the types of plants can be effectively present in the network. If managers believe that their network would benefit from plants spreading best practices, they should identify which plants have active and hosting capabilities, and foster these plants in their network. However, the hosting network players seem to be a result of the past, while the existence of the active network players can be stimulated. Our research indicates what it takes to develop an active network player. On the other hand, the manager may find it wise to have some isolated plants or receivers (types A and B). These are quite mobile building blocks of the network. Reducing the number of isolated plants or receivers does not impact the potential for transferring knowledge. As such, the presence of isolated plants and receivers gives the manager some structural flexibility in managing his network. To the plant manager, the research shows the danger of a protective attitude toward the exchange of knowledge. The isolated position taken by these plants may well result in a difference in view between plant managers and company managers about the strategic future of the plant. 7. Limitations and Future Research An important limitation of the research is the focus on the intracompany network relationships. While we acknowledge that intercompany network relationships are important in creating sustainable competitive advantage, we have limited our research to the network relationships between units of the same company. Whether the hosting and active network players are also tightly embedded in the external, intercompany network with suppliers, customers, and other network partners remains to be studied. Second, our research describes the strategic role played by plants in international plant networks. It identifies those plants that develop knowledge and capabilities and that transfer this knowledge to the other plants in the network. The research does not explain how this knowledge is developed, nor does it describe the mechanisms used for the diffusion of this knowledge and their effectiveness. Also, as stated earlier, the research is static and raises questions as to the further evolution of the plants and of their position in the network. This is an area of future research. The absence of significance in the difference in performance in the network typology may point at a lack of difference in performance. However, it may as well be a consequence of the performance measure that has been used, which is static and rather restrictive (that is, performance relative to the target set for the plant) and operationalized as a perceptual measure. There is definitely still a need to study the relationship between plant performance and the position the plant plays in the manufacturing network. Also, we did not make any assertions about the relationship between the portfolio of plants in terms of their network type and the performance of the company. We hypothesize that the optimal portfolio Vereecke et al.: Typology of Plants in Global Manufacturing Networks 1748 Management Science 52(11), pp. 1737–1750, © 2006 INFORMS of plants is contingent on the company’s competitive environment. However, this needs to be studied. As mentioned in the Methodology section (§3), this paper is based on case research. While one of the major advantages of case research is the depth of the information that can be collected, its major disadvantage is the limitation in sample size, and therefore the potential limitation in external validity. However, we are convinced that the careful selection of the cases from a diversity of industries improves the external validity of the work. The cases have been limited to companies headquartered in Europe to avoid cultural differences between the cases. Whether the conclusions still hold in multinationals headquartered in other continents is unexplored and can be subject to future research. Finally, the research focuses on manufacturing companies only. Whether a similar typology can be developed for service companies is an open question. 8. Conclusion In the research, network analysis has been used as a methodology for understanding the position of plants in international manufacturing networks. The focus has been primarily on the intangible knowledge network, and secondarily on the physical, logistic network. A typology of plants in a manufacturing network has resulted from the research. Four types of plants, with a different strategic role, different characteristics, and different perspectives for the future have emerged. The typology indicates that flows of knowledge between plants seem to be reciprocal, and that there is a clear correlation between tangible and intangible flows in the network. The driver behind intensive network relations may be either heritage or a deliberate investment in capabilities inside the plant. Anyhow, building network relationships takes time. We have also observed that the future of plants that are tightly embedded in the network is more stable and secure. Overall, this leads us to believe that in managing international networks of plants, managers can balance long-term knowledge development and medium-term flexibility. In approving investments in the network relationships, they allow some of the plants to play an active role in the creation and diffusion of knowledge in the network, thus creating long-term competitive advantage. The other plants provide the manager with strategic flexibility. Their role in the network can be adapted in the medium term, according to the changing needs of the business. Appendix 1. Interrater Reliability Scores on Perceptual Measures Construct Factor Item ICC Strategic role today 0.85 Strategic role 5 y Ahead 0.83 Operational autonomy Strategic autonomy Logistics Developing a master production schedule Developing material and capacity plans Developing the shop floor schedule Developing sales forecasts Placing purchasing orders Managing inventories 0.81 0.78 0.70 0.89 0.80 0.70 Development and engineering Developing new products Making changes to existing products Developing new production processes Making changes to existing production processes 0.74 0.77 0.78 0.79 Operations of the plant Decision to develop a new product Decision to make changes to an existing product design Selection of a new supplier Decision to introduce a new planning and control system Choice of standards, goals, and performance measures for quality management 0.69 0.76 Design of the plant Decision to develop a new production process Decision to make changes to an existing production process Choice of technology 0.77 0.80 0.70 0.76 0.78 0.73 Vereecke et al.: Typology of Plants in Global Manufacturing Networks 1749 Management Science 52(11), pp. 1737–1750, © 2006 INFORMS Appendix 1. Continued. Construct Investment Factor Process investment Investment in planning Managerial investment New product investment Plant capabilities Level of resources Not included in the analyses Performance relative to target Time performance Cost and quality performance Not included in the analyses Item ICC Setup time reduction Plant automation Process analysis Productivity improvement Throughput time reduction Material and/or capacity planning Just-in-time systems Statistical process control Supplier partnerships Total quality management Employee participation programs New product development 0.67 0.73 0.73 0.75 0.85 0.57 0.72 0.87 0.81 0.89 0.76 0.77 Capabilities in developing new products Managerial capabilities Level of technical resources 0.66 0.62 0.34 Manufacturing throughput time (from start until finish of production) Service level (on-time delivery to customers) Delivery lead time (from customer’s order until delivery) Average defect rates at the end of manufacturing Average unit production costs for a typical product Productivity of direct production workers Overall product quality as perceived by the customers Rate of new product introduction Equipment setup time 0.61 0.75 0.60 0.75 0.80 0.78 0.69 0.47 0.54 Note. For most of the items the ICC exceeds 0.60, which is the cutoff value suggested by Boyer and Verma (2000). For the item “investments in materials and/or capacity planning,” the ICC reaches 0.57. However, because this is very close to the cutoff level, the item has been retained in the analyses. The ICC cutoff level of 0.60 was not reached for the items “level of technical resources,” “rate of new product introduction,” and “equipment setup time.” Consequently, these items have been omitted from the analyses. Appendix 2. Overview of Interview Comments Cluster A Independent 2× Local 2× Improved/learning 4×; problem solvers 2× Manufacturing capabilities 7× Motivated 2×; creative Development for their own Product focused Cluster B Only executes 2× Some development 9×; a lot of development 1× Expert (in quality, service, material handling, CIM, energy savings) Limited; simple Complex; difficult; below expectation Local market 7×; Local improvements; local culture Needs help 2×; receives (technical) support 3× Lives its own life; goes its own way; distance Lack of motivation; inflexible management; management problems 2×; lack of skills 4×; Insufficient experience; negative mentality; counterproductive mentality; mentality is to accept Problems as they come; social climate has improved Crew of Belgian managers; no own management; group of expatriates; satellite plant 2×; Management input from HQ; strong liaison manager in other plant Cluster C Pilot plant 1×; test site 1×; development site 4× Center of excellence 3×; center of competence Product know-how 3×; process know-how Training center Supports other plants 2×; motor for all products 1× Close to HQ; home player; mother plant 1× Quite motivated to experiment Lack of focus Lack of investment Satellite 1× Product specialist Cluster D Center of excellence 2×; development center; pilot plant 3× Think tank; generator of ideas Atmosphere of activity; do-spirit; enthusiasm; happy to experiment Motor of the other plants; engine Gives technical assistance; high tech; specialist; process know-how Close to HQ 1× 1750 References Aldenderfer, M. 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