Perceptions of General Variability of Social Groups

A model of perceived general variability (dual predictor model) is proposed. It postulates that perception of group variability is an additive function of similarity and difference among members of a group. The basic tenet of the model was tested in an experiment in which the amounts of similarity and difference information among group members were independently manipulated. Consistent with the model, it was found that the greater the amount of difference, the more variable the group was perceived to be, and that the greater the amount of similarity, the less variable the group was perceived to be. There was no interaction effect due to similarity and difference information, suggesting the additive nature of the effects. In contrast, perceived dimensional variability was directly influenced only by the amount of difference among group members. The results are inconsistent with the hypothesis that amount of information positively affects perceived variability.