Why do faultlines matter?: A computational model of how strong demographic faultlines undermine team cohesion

Lau and Murnighan (LM) suggested that strong demographic faultlines threaten team cohesion and reduce consensus. However, it remains unclear which assumptions are exactly needed to derive faultline effects. We propose a formal computational model of the effects of faultlines that uses four elementary social mechanisms, social influence, rejection, homophily and heterophobia. We show that our model is consistent with the central hypotheses of LM's theory. We also find that negative effects of faultlines can be derived even when - unlike LM - we assume that initially there is no correlation between the demographic characteristics and the opinions of team members. (c) 2007 Elsevier B.V. All rights reserved.