This bias was found to be unrelated to the number of group and non-group members individuals knew. One might think that people thought members of their own groups were more varied and different simply because they knew them better and thus have more information about ingroups, but this is actually not the case. The out-group homogeneity bias was found between groups such as "men" and "women" who obviously interact frequently. However, this concept has been challenged due to some cases in which in-groups view themselves as homogeneous. Researchers have postulated that such an effect is present when viewing a group as homogeneous helps to promote in-group solidarity. Experiments on the topic found that in-group homogeneity is displayed when people who highly identify with a group are presented with stereotypical information about that group.
Self-categorization theory Self-categorization theory attributes the outgroup homogeneity effect to the differing
contexts that are present when perceiving outgroups and ingroups. For outgroups, a perceiver will experience an intergroup context and therefore attend to differences between the two groups. Consequently, less attention is paid to differences between outgroup members and this leads to perceptions of outgroup homogeneity. When perceiving ingroup members a perceiver may experience either an intergroup context or an
intragroup context. In an intergroup context the ingroup would also be predicted to be seen as comparatively homogeneous as the perceiver attends to the differences between "us" and "them" (in other words, depersonalization occurs). However, in an intragroup context the perceiver may be motivated to attend to differences with the group (between "me" and "others in the group") leading to perceptions of comparative ingroup
heterogeneity. As perceivers are less often motivated to perform intra-group outgroup comparison, this leads to an overall outgroup homogeneity effect. The self-categorization theory account is supported by evidence showing that in an intergroup context both the ingroup and outgroup will be perceived as more homogenous, while when judged in isolation the ingroup will be perceived as comparatively heterogeneous. Within the same tradition it was also hypothesised that an ingroup homogeneity effect would emerge on ingroup defining dimensions for both minority and majority group members. This too was empirically supported. Recent research also has reaffirmed that this effect of in-group homogeneity on in-group defining dimensions and out-group homogeneity on out-group defining dimensions may occur because people use their ratings of perceived group variability to express the extent to which social groups possess specific characteristics. ==See also==