Abstract

The present research investigates the motivational basis of the ingroup over-exclusion effect (Leyens and Yzerbyt, 1992). According to the ingroup overexclusion, when participants are called to decide about exemplars' group membership, they tend to be particularly careful in including others within their own social group, and prefer to include exemplars in the outgroup. The effect has been explained in terms of a motivation to protect the ingroup social identity. In the present studies, we manipulated the importance devoted to the ingroup-outgroup distinction, that could be either high (Experiment 1) or low (Experiment 2). The experimental paradigm is based on a recognition memory task, and errors are taken as the main dependent variable. The hypotheses, supported by the obtained results, are that only when participants are faced with a relevant social identity, the ingroup overexclusion occurs. On the other hand, in the case of an irrelevant categorization, it seems that different processes, such as the false consensus bias, are at work, leading to an overinclusion in subjects' own group.