Ingroup Bias

Ingroup bias, also called in-group favoritism or in-group-out-group bias, is the tendency to favor members of one's own group over people outside it, a pattern that shows up in how people evaluate others, allocate resources and behave in many other everyday situations. The sociologist William Sumner first proposed in 1906 that humans naturally form groups and hold an inherent preference for their own, observing that each group tends to nourish its own pride while regarding outsiders with comparative contempt. Two main theories are offered to explain the bias: realistic conflict theory, which holds that competition between groups for scarce resources produces favoritism and conflict, and social identity theory, which attributes the behavior to a basic psychological drive to maintain a positive and distinct social identity. The bias appears consistently across cultures and tends to intensify when a group's members are more interdependent on one another, and research also finds it can emerge simply from the process of forming a group around even a trivial shared trait.