Social Identity as Social Glue: The Origins of Group Loyalty.

Abstract
In 3 experiments, the authors investigated the role of social identity in fostering group loyalty, defined as staying when members can obtain better outcomes by leaving their group. In Experiment 1, high (vs. low) identifiers expressed a stronger desire to stay in the group in the presence of an attractive (vs. unattractive) exit option. Experiments 2 and 3 replicated this basic finding and tested several explanations. The results suggest that high identifiers' group loyalty is better explained by an extremely positive impression of their group membership (group perception) than by a justification of previous investments in the group (self-perception) or their adherence to a nonabandonment norm (norm perception). Hence, social identity seems to act as social glue. It provides stability in groups that would otherwise collapse.