The influence of personal and collective self-esteem on strategies of social differentiation.

The present study distinguished between personal self-esteem (PSE) and collective self-esteem (CSE) as determinants of in-group bias in an intergroup context. Subjects performed a group task, the product of which they subsequently evaluated ('own' group), along with solutions allegedly produced by another 'in-group' (similar nationality), and an 'out-group' (different nationality). This provided the opportunity for intragroup discrimination (own vs. in-group), and both direct (own vs. out-group) and indirect (in-group vs. out-group) strategies of intergroup discrimination. It was predicted that subjects high in CSE would differentiate more than subjects low in CSE, both directly and indirectly, but that intergroup discrimination would also result from high PSE. The relationship between the in-group and out-group was also manipulated by varying the salient out-group. It was predicted that subjects motivated to enhance social identity (high CSE) would differentiate more, directly and indirectly, when the out-group was seen as having a more competitive relationship with the in-group. Although this manipulation was unsuccessful, a follow-up suggested that the out-group predefined as less competitive was actually a more relevant comparison group in the context of the task, which is consistent with effects of this manipulation. Overall PSE and CSE were both found to influence differentiation at the intragroup and intergroup level, both independently and interactively. However, whereas high PSE led to greater positive differentiation, low CSE had this effect, and a combination of high PSE and low CSE produced the most consistent pattern of positive in-group differentiation across both out-group conditions. Possible mechanisms which account for this pattern are discussed and the relationship between dimensions of self-esteem and group differentiation is reappraised in the light of these findings.