Mere arbitrary group membership, with no interaction, triggers in-group favoritism

Evidence

In the basic paradigm the subjects (both children and adults have acted as subjects in the various studies) are randomly classified as members of two nonoverlapping groups— ostensibly on the basis of some trivial performance criterion. They then make “decisions,” awarding amounts of money to pairs of other subjects (excluding self) in specially designed booklets. The recipients are anonymous, except for their individual code numbers and their group membership (for example, member number 51 of the X group and member number 33 of the Y group). The subjects, who know their own group membership, award the amounts individually and anonymously. The re-sponse format of the booklets does not force the subjects to act in terms of group membership. — John T. Jost and Jim Sidanius, Political Psychology, 2704

Categorization

• XREF: connects to: Mild individual in-group preference generates macro segregation spontaneously — David Theo Goldberg, The Threat of Race: Reflections on…, 383; Merely categorizing people into us and them generates in-group favoritism and out-group devaluation; Mere group membership suffices to trigger self-esteem-linked favoritism. — Anthony G. Greenwald and Mahzarin R. Banaji, Implicit Social Cognition: Attitudes,…, 126 (+1 more)