“They’re all the Same!”...But for Several Different Reasons

People often get confused between members of the same social group because “they all look the same!” In a recent review, Constantina Badea and I looked at the various reasons for this group homogeneity effect.

 
One reason is that group members actually do look the same as one another: Try identifying the culprit in a line-up of the Queen’s Guards!

Another reason is that people, especially Westerners, are motivated to perceive people in their own groups as individuals. This perceived in-group heterogeneity lets you express your individuality and distance yourself from your group's negative aspects.

It also matters what kind of group is being judged. There is a tendency to judge people in small groups, low status groups, and low power groups as being relatively similar to one another.

Finally, it matters what dimensions are being used to judge the groups. Group members tend to be rated as being similar to one another when they are judged on stereotypical dimensions as opposed to nonstereotypical or counterstereotypical dimensions (e.g., men judged on the dimension “adventurous” rather than "sensitive").

So, whether or not “they all look the same” depends on their actual variability, whether you are one of them, how numerous and powerful they are, and what kind of dimensions you’re judging them on.

For further information, please see the following journal article: Rubin, M., & Badea, C. (2012). They're All the Same!. . . but for Several Different Reasons: A Review of the Multicausal Nature of Perceived Group Variability Current Directions in Psychological Science, 21 (6), 367-372 DOI: 10.1177/0963721412457363

A self-archived version of this paper is available here.

Please click here for a collection of research papers investigating perceived group variability.