Out-Group Homogeneity

The out-group homogeneity effect is the perception that members of an out-group are more similar to one another than members of one's own in-group are, captured in the summary they are alike, we are diverse. Because perceivers form impressions of a group's diversity around its central tendencies or typical attributes, judgments of out-group stereotypicality tend to be overestimated, supporting the broader view that out-group stereotypes are often overgeneralizations; the effect, sometimes called out-group homogeneity bias, sits within a wider meta-theoretical debate in social psychology over whether heightened perceptions of in-group and out-group homogeneity should be treated as a cognitive bias and error or as a normal, often adaptive, form of social perception. It has been documented across a wide variety of social groups, from political and racial groups to age and gender groups, and it forms part of a broader field of research into perceived group variability, including related in-group homogeneity effects and other perceived-variability effects tied to a group's power, status or size.