Personal identity and social identity: A comparison between self-categorization theory and the model of egocentric social categorization

In this study the different hypotheses deriving from self-categorization theory (Turner et al., 1987) and from the model of egocentric social categorization (Simon, 1993) were tested. These hypotheses concern ingroup bias and the outgroup homogeneity effect. Using the paradigm of the minimal groups, three experimental conditions were created. In all of them, participants (n = 74) were informed that both the members of the ingroup and the members of the the outgroup, subjects included, would have to solve problems of a cognitive nature: cultural, linguistic, mathematical. In the first condition, quasi-intergroup, the ingroup was presented as an aggregate and the outgroup as a group; there was, moreover, intragroup competition. In the second, mixed, ingroup and outgroup were both groups; in this condition there was both intragroup competition and intergroup competition. In the third condition, intergroup, the only competition present was that between the two groups. The main factors of the experimental design, between subjects, were: relations (quasi-intergroup, mixed, intergroup) and target (ingroup, outgroup). Before proceeding to the solution of the problems, which were anticipated but never presented, the participants received information, sequentially, on the 50 members of the ingroup or on the 50 members of the outgroup, regarding their IQs. Participants were then submitted to free recall tests; they evaluated the mean IQs of the two groups and judged their homogeneity. Results confirm the principle of functional antagonism between personal and group levels of self-categorization. Moreover, they demonstrate the validity of the hypothesis that ingroup bias is revealed only when the more salient identity is social identity. The results confirm the hypotheses derived from self-categorization theory, not those derived from the model of egocentric social categorization.