Minimal group paradigm

In-group favoritism is easily prompted

The minimal group paradigm is a method employed in social psychology. Although it may be used for a variety of purposes, it is best known as a method for investigating the minimal conditions required for discrimination to occur between groups. Experiments using this approach have revealed that even arbitrary distinctions between groups, such as preferences for certain paintings, or the color of their shirts, can trigger a tendency to favor one's own group at the expense of others, even when it means sacrificing in-group gain.

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