توانمندسازی تیم ها از طریق روابط شبکه اجتماعی

Effective teamwork and knowledge coordination are becoming increasingly important for all kinds of organizations given the growing use of teams to tackle competitive challenges and sustain competitive advantage. In this study, we develop and validate a model of how two types of social network ties – expressive and instrumental – contribute to team efficacy and performance, mediated by three dimensions of a transactive memory system (TMS) – specialization, credibility and coordination within teams. We test the model in an empirical study drawing on data from 66 teams in a variety of organizations. The results suggest that both instrumental and expressive ties within teams can facilitate the formation of TMS and the three dimensions of TMS are all, even though to different extents, positively related to team efficacy. Team efficacy is also a powerful predictor of team performance. The findings in our study bridge the literature gap about social networks and TMS and explain the underlying process and mechanisms by which social network ties exert their influence on team outcomes. The results have implications for organizations that wish to leverage teams to take advantage of team members’ differentiated expertise and coordinate their work more effectively and efficiently.

In today's rapidly changing and increasingly competitive business environment, teams are widely employed in organizations (Gully, Incalcaterra, Joshi, & Beaubien, 2002), since teams can increase organizational capability, flexibility and responsiveness (Griffith, Sawyer, & Neale, 2003). The increased emphasis on teams has aroused substantial interest in exploring determinants of team performance for both organizational researchers and practitioners (Kozlowski and Ilgen, 2006 and Zhang et al., 2007). Social network approaches to team research have gained particular popularity (Balkundi and Harrison, 2006 and Tjosvold et al., 2005). Researchers have articulated that social ties have the potential to facilitate the flow of all kinds of resources within teams, which correspondingly determines the success of teams (Balkundi & Harrison, 2006). However, little effort has been made in previous research to pinpoint the mechanisms through which social relationships have impacted team outcomes (Balkundi & Harrison, 2006). Knowledge is indispensable to contemporary organizations, and the importance of knowledge is particularly noticeable for teams given their need to create, share and apply knowledge (Choi, Lee, & Yoo, 2010). Accordingly, knowledge management (KM) has become an important issue in organizations since only when knowledge is managed effectively can organizations increase their innovativeness and responsiveness to competitive threats (Alavi & Leidner, 2005). In particular, knowledge sharing and application are widely recognized as the key determinants of team performance (Choi et al., 2010 and Janhonen and Johanson, 2011). Previous researchers have argued that social relationships might have an impact on KM outcomes and so called for further research into the effect of relationships in KM (Argote, McEvily, & Reagans, 2003). In this study, applying the input-process-output model, we concentrate on the impact of social ties on team outcomes through the perspective of knowledge coordination processes within teams. Two basic forms of interpersonal relationships, involving instrumental and expressive ties, have been distinguished by social network researchers (Balkundi & Harrison, 2006). These two types of ties remain theoretically distinct, as the former is work related, while the latter is more associated with socio-emotional attachment. Previous scholars have explicitly called for new research to pay attention to the expressive dimensions of relationships in networks and suggest that appropriate expressive ties for instrumental purposes might have unintended consequences on performance related outcomes (Cross & Cummings, 2004). As knowledge is a critical asset for teams and is often distributed across team members, ensuring that the right knowledge is available to the right person at the right time is vital if teams are to be successful (Kwan & Balasubramanian, 2003). In order to address the issue of knowledge coordination and utilization within teams, the transactive memory system (TMS) (Wegner, 1987) has been proposed as an effective knowledge processing technique. A TMS refers to a specialized division of cognitive labor that develops within a team regarding team members’ encoding, storing and retrieving of information (Wegner, 1987). Many studies have confirmed that a well-developed TMS can indeed improve team outcomes (Kanawattanachai and Yoo, 2007, Lewis, 2004 and Zhang et al., 2007). TMS is considered to have three aspects: specialization, credibility and coordination (Akgun et al., 2005, Kanawattanachai and Yoo, 2007, Lewis, 2003, Moreland and Myaskovsky, 2000 and Zhang et al., 2007). These researchers argue that TMS has the potential to allow team members to develop and be aware of each other's specialized expertise (specialization), confide in each other's competence and reliability (credibility), and integrate each other's knowledge together in a coordinated manner (coordination). Most previous research simply bundled these three aspects together, which may have caused difficulties in interpreting the real meaning and effect of TMS on team outcomes. Recent studies have tried to separate these three dimensions since specialization and credibility are cognitive processes, while coordination is a behavioural process; the three aspects are thus theoretically distinct (Kanawattanachai & Yoo, 2007). In order to better understand the antecedents and outcomes of TMS, we also study these three dimensions separately. Based on the input-process-output model of teamwork, recent studies have turned attention to another kind of intermediate mechanism – the emergent state – that underpins the impact of team input on outcomes (Ilgen et al., 2005, Marks et al., 2001 and Srivastava et al., 2006). Team emergent state is different from team processes; team processes are the means by which members work interdependently to utilize various resources through cognitive, verbal and behavioural activities, while emergent state describes “cognitive, motivational, and affective states of teams, as opposed to their member interaction” (Marks et al., 2001, p. 357). Srivastava et al. (2006) have explicitly articulated the importance of incorporating both team process and emergent state in a single model and called for future research to do so. With respect to the relationship of team processes and emergent state, researchers have argued that a team's emergent state can be influenced by team cognitive processes (Marks et al., 2001). One emergent state – team efficacy – has drawn much attention, and two recent meta-analyses (Gully et al., 2002 and Stajkovic et al., 2009) provide compelling evidence that team efficacy is significantly related to team performance. Previous research has also indicated that TMS may contribute to team efficacy (Gibson and Earley, 2007 and Mannix et al., 2002), which indicate that TMS not only has a direct effect on team performance, but the effect may be also partially mediated by promoting the team efficacy. Nevertheless, little research has empirically investigated the relationship between TMS and team efficacy. However, such an investigation may help us better understand the effect of TMS on team performance and so provide more insights into how team performance can be improved. All of these factors stimulate our interest in research on the mediating effect of team efficacy on the relationship between three dimensions of TMS and team performance. In general, in this study, we aim to answer the following research questions: (1) How do instrumental ties and expressive ties influence team outcomes through TMS and team efficacy? (2) How may TMS contribute to team outcomes through the mediating role of team efficacy? We use team efficiency and team effectiveness to evaluate team outcomes in this study. In answering these questions, this paper contributes to the previous literature in several ways. Firstly, we add to the social network literature by examining the team processes through which social networks exert their influence on team outcomes. Secondly, we investigate the mediating role of team efficacy among TMS and team performance. Thus, the relationship between team processes, team emergent state and teamwork outcomes are much clearer. Thirdly, we separate the three dimensions of TMS so as to enrich our understanding of the development and outcomes of TMS. Following this introduction, we review the relevant literature and justify the above arguments in a theoretical development where we construct the research model and develop the hypotheses. The empirical test of the research model will also be described. The results will then be presented, followed by the discussion of the theoretical and managerial implications, and future research directions.

5.1. The effects of social ties on specialization The effects of two kinds of social network ties on three aspects of TMS were investigated. Instrumental ties and expressive ties are both significantly related to all three aspects of TMS. This suggests that both types of ties may facilitate the development of a knowledge map of who knows what. Further, both types of ties can promote specialized expertise formation within in teams. The significantly positive impact of expressive ties on specialization is contrary to the suggestions of Kanawattanachai and Yoo (2007) that expressive ties among team members may cause members to focus primarily on the surface-level diversity, potentially hindering their ability to take advantage of each other's deep work related expertise and knowledge. Expressive ties have a stronger effect on specialization than do instrumental ties because expressive ties are more focused on the transfer of tacit knowledge (Zhou et al., 2010). However, we found that instrumental ties exert more influence on specialization than expressive ties. This can be understood easily, since instrumental ties are work-related and can release more expertise information. 5.2. The effects of social ties on coordination We also found that both types of social ties can lubricate and promote coordination process. However, instrumental ties are more important than expressive ties. One reason for this may relate to the fact that expressive ties may lead to similar perspectives towards work (Gibbons, 2004) and so knowledge redundancy (Reagans & Zuckerman, 2001). Thus, for team coordination which requires diverse knowledge from different team members, instrumental ties can provide more diverse task based knowledge, which is more important than the benefits of mutual social support derived from expressive ties. 5.3. The effects of social ties on credibility The significant impacts of instrumental and expressive ties on credibility are also confirmed, which is congruent with previous research (Zhou et al., 2010). The results also indicate that expressive ties are more important for the formation of credibility. We argue that though credibility is formed based on the competence of other members, it is still an affect-laden construct. Besides, as we mentioned before, expressive ties often link individuals who may perceive social similarity with each other (Gibbons, 2004), since based on self-categorization theory, individuals are more likely to aggregate themselves with others in the light of objective attributes (Turner, Hogg, Oakes, Reicher, & Wetherell, 1987). Cultural-ethnic similarity is recognized as an important antecedent of cognition-based trust as persons will be more ready to trust a person in the same cultural group rather than a person in a different cultural group (McAllister, 1995). 5.4. The effects of TMS on team efficacy The significant impacts of the three dimensions of TMS on team efficacy are confirmed. Among the three dimensions, coordination plays the most important role for team efficacy; the significance of credibility is slightly lower than coordination and specialization contributes the least influence. The results support the notion that coordination is the pivotal dimension of TMS (Kanawattanachai & Yoo, 2007) and imply that not only can the formation of TMS give inspiration to team construction and teamwork processes, but it can also promote a team's motivational state. It is clear that team efficacy has a significant relationship with team performance. 5.5. The mediation effect of team efficacy between TMS and team performance Interestingly, we found that team efficacy fully mediated the relationship between coordination and team performance, but only partially mediated the impacts of specialization and credibility on team performance. Part of the reason for the mediating role of team efficacy may be that even if TMS is well developed in teams, if the team members do not have high certainty that they can achieve the collective goal, they may not want to exert much effort to take advantage of others’ expertise. The amount of effort is an important precursor to team performance (Bandura, 1997). 5.6. The effects of task interdependence on team performance In this study, we also found that the control variable – task interdependence – has a significant effect on team performance. A possible explanation of this effect may be that task interdependence is the glue that holds different team members together; when team members are highly interdependent with each other, team members will be more motivated to put their efforts together to perform well (Janz, Colquitt, & Noe, 1997). Correspondingly, the team performance will be high. Moreover, at a lower level of task interdependence, team members may focus more on individual accomplishment rather than on team accomplishment (Aubé & Rousseau, 2005). Thus, when task interdependence is high, all team members may strive to the same direction in order to better accomplish the team collective goal.