Expertness Diversity and Interpersonal Helping in Teams: Why those who Need the Most Help End Up Getting the Least

This article develops and tests a multilevel theory of the intragroup dynamics and performance outcomes associated with diversity in levels of member expertise—“expertness diversity”—in task-oriented teams. Drawing from theories of power and dependence, we argue that in groups where members differ in their perceived expertness, members will be more committed to and more likely to help those seen as more expert, a dynamic that frustrates intragroup learning and compromises group performance. These hypotheses were strongly supported in a multiperiod, multilevel analysis of social relations and performance outcomes in a sample of student research teams.