Perceptions of Ingroup and Outgroup Variability: A Meta-Analytic Integration

Abstract This article reports the results of a meta-analytic integration of previous research on perceptions of ingroup and outgroup variability. The following patterns were observed: The tendency to perceive greater variability for the ingroup relative to the variability perceived for the outgroup (relative heterogeneity) was demonstrated to be a significant but small effect. The basic relative heterogeneity effect is the result of a small shift away from the midpoint of the scale toward homogeneity for the outgroup, coupled with a smaller, slight shift away from the midpoint of the scale toward heterogeneity for the ingroup, in addition, perceptions of group variability were demonstrated to vary in predictable and interesting ways. For example, relative heterogeneity decreases as the relative size of the ingroup decreases, producing a relative homogeneity effect on the part of small minorities. Relative heterogeneity is strongest when the ingroup and outgroup comprise real, enduring groups, and weakest when the ingroup and outgroup comprise artificial, laboratory-created groups. Discussion considers the implications of these results for the various proposed mediating mechanisms for perceptions of group variability, and for an understanding of the phenomenology of being in a group.