De la diversité des équipes : étude du rôle des vecteurs de failles sur la performance

Despite more than fifty years of research since the first empirical studies on diversity in work teams began, it remains difficult to draw clear and coherent conclusions on the nature and direction of the relationships between diversity and group performance. This observation has led a number of researchers to formulate recommendations to help break the deadlock. On the one hand, organizations are relying more and more on teams to ensure their efficacy, while on the other hand, diversity continues to increase along with immigration and knowledge specialization. In such a context as this, it becomes particularly relevant to pursue research efforts in terms of these recommendations, in order to clarify the impact of diversity on performance. This thesis fits within a growing research stream that has answered the call of its researchers, aiming to evaluate the effects of the structure of diversity rather than simply the amount of diversity within teams. The Faultline theory (Lau & Murnighan, 1998) has allowed for major progress to this effect. Faultlines are hypothetical dividing lines that split a team when numerous diversity dimensions align to create relatively homogeneous subgroups. However, certain contradictory empirical results shed light on the importance of considering the entirety of recommendations on diversity research that have been brought forth. Through the faultline lense, this thesis aims to deepen our understanding of the role of diversity in team performance, by putting in practice these diverse recommendations in order to 1) examine the role of mediating mechanisms as well as moderating effects that could play a part in this relationship, 2) specify the typologies of teams and performance, and 3) consider the influence of the context within which work teams operate. The first article consists of an empirical synthesis that aims to specify the differential effects that various faultlines can have on various types of performance, and to evaluate the moderating role played by the type of team studied. The results from this meta-analysis conducted on a sample of 38 studies comprising 3046 teams, shed new light on those previously reported and reveal that faultlines have a negative effect on behavioral performance but not on outcome performance. Moreover, the type of team studied moderated these relationships such that they are more strongly negative for project teams than for management teams. The second article empirically evaluates the effect of informational faultlines on a specific performance dimension, team adaptability, by examining the mediating role of implicit coordination, as well as the moderating effect of role and responsibility clarity. A moderated mediation analysis, conducted on a sample of 14 project teams, revealed that implicit coordination mediates the negative relationship between informational faultlines and team adaptability. This relationship is more strongly negative when the roles and responsibilities of the team members are either clear or very clear. The theoretical and practical implications of these results are subsequently discussed.

Keyphrases: Performance, Coordination, Faultlines, Diversity, Project teams, Adaptability, Shared mental models