Resumen de La confiance dans les décisions collectives: une question de garanties

Maria Augustinova, Ewa Drozda-Senkowska, Barbara Lasticova

• Past research suggests that a consensual decision made by a heterogeneous group is perceived as more credible than a consensual decision made by a homogeneous group. In this paper we focus on the origine of this heuristic of heterogeneity and on limits of its use.

  We suggest that the credibility of a collective decision is not only a function of information about group composition (heterogeneous vs. homogeneous) but also depends on other information, namely information about the group decision-making process, whether it is available or inferred. Results of three studies are consistent with this hypothesis : the effect of information about group composition on credibility ratings is moderated by the information about its decisional consistency (Study 2) and about the efficiency of information sharing during a group discussion (Study 3) . Credibility ratings are only a function of the heterogeneity heuristic when no explicit information about group decision-making process is given to individuals judging the credibility of collective decision (Study 1).