In-group

In sociology and social psychology, an ingroup is a social group to which a person psychologically identifies as being a member. By contrast, an outgroup is a social group with which an individual does not identify. For example, people may find it psychologically meaningful to view themselves according to their race, culture, gender, age or religion. It has been found that the psychological membership of social groups and categories is associated with a wide variety of phenomena.

The terminology was made popular by Henri Tajfel and colleagues during his work in formulating social identity theory. The significance of ingroup and outgroup categorization was identified using a method called the minimal group paradigm. Tajfel and colleagues found that people can form self-preferencing ingroups within a matter of minutes and that such groups can form even on the basis of seemingly trivial characteristics, such as preferences for certain paintings.

The psychological categorization of people into ingroup and outgroup members is associated with a variety of phenomena. The following examples have all received a great deal of academic attention.

This refers to the fact that under certain conditions people will prefer and have affinity for one’s ingroup over the outgroup, or anyone viewed as outside the ingroup. This can be expressed in one's evaluation of others, linking, allocation of resources and many other ways.

Discrimination between ingroups and outgroups is a matter of favoritism towards an ingroup and the absence of equivalent favoritism towards an outgroup. Outgroup derogation is the phenomenon in which an outgroup is perceived as being threatening to the members of an ingroup. This phenomenon often accompanies ingroup favoritism, as it requires one to have an affinity towards their ingroup. Some research suggests that outgroup derogation occurs when an outgroup is perceived as blocking or hindering the goals of an ingroup. It has also been argued that outgroup derogation is a natural consequence of the categorization process.

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