Diversity and small group decision making: Towards a social identity framework for studying the effects of task-related differences in dyads and groups.

Summary Diversity has become a topic of interest in social psychological research as well as in applied contexts due to the growing number of work situations in which diverse (e.g. ethnically diverse or multi-functional) teams are responsible for achieving collective goals. When working together with other people as a team, people can differ from each other in many ways. Central to this thesis are differences that are directly related to the task that people have to perform together (Pelled, Eisenhardt & Xin, 1999; Bunderson, 2003). Team members can possess different knowledge and skills, prefer to use different decision making strategies, or personally aim for different work or career goals. I have focused on the impact of these three task-related differences - which are referred to as informational diversity, work style diversity and work goal diversity - on both group and dyadic decision making. While the social identity/self-categorization perspective (Tajfel, 1972; Tajfel & Turner, 1986) is generally used to explain the negative consequences of diversity in groups (e.g. Harrison, Price, Gavin & Florey, 2002), I posited the theoretical argument that social identity processes can also lead group members to evaluate their differences in a positive way. The central aim of this thesis was to show that group members can form a common identity based on the very fact that they agree and expect to differ from each other. As a result they come to consider their differences as a feature they share which is prototypical for their group. In seven experimental studies I sought to demonstrate that this would most likely happen when these differences were expected to occur prior to collaboration, or when group or dyad members differ from each other in multiple ways during collaboration (as this enables them to clearly perceive their mutual differences), rather than when they only differed partially from each other and still remain similar to a certain extent.