Outgroup Homogeneity Effect: Definition and Examples

outgroup homogeneity effect examples and definition

The outgroup homogeneity effect is a cognitive bias in which people mistakenly perceive outgroup members as being a homogenous group.

In other words, it is the perception that members of an outgroup are identical to one rather. It ignores the fact that even though people are members of a certain group, they still may possess very unique characteristics and opinions.

As a result, an “us” versus “them” mentality is created between different groups, each with opposing narratives, and each harbors generalized and false assumptions of the outgroup.

A simple example of the outgroup homogeneity effect is a white person thinking “all Asians look the same” or a privileged person thinking “all poor people are dirty.”

Outgroup Homogeneity Effect Definition

Social psychologist Gordon Allport (1897-1967) was one of many academics that conducted studies on intergroup relations and the nature of prejudice.

Allport (1954) defines it simply, intergroup prejudice consists of negative opinions against an outgroup without sufficient evidence.

He argues that unfounded bias of the outgroup leads directly to misjudgments of people from different backgrounds, and contributes directly to the formation of stereotypes. He writes:

“In strict logic, an in-group always implies the existence of some corresponding out-group. But this logical statement by itself is of little significance. What we need to know is whether one’s loyalty to the in-group automatically implies disloyalty, or hostility, or other forms of negativism, toward out-groups” (Allport, 1954, p. 41).

Similarly, Simon (1992) notes that individuals, who identify as a minority, have challenges sustaining their self-image.

To combat this, Simon (1992) suggested that the in-group view their group as a unified team in order to foster a feeling of solidarity. This notion of togetherness enables them to take on a biased viewpoint of outgroups to enhance their self-esteem (pp. 4-8).

Output Homogeneity Effect Examples

  1. Political division in the USA – This effect was especially apparent during the polarizing 2016 election of ex-United States president Donald Trump; it continued through his 4-year presidency, and the dramatic division between political party ideals has cemented in American society.
  2. Religious conflict – Longstanding differences in opinion and fighting between Muslims and Jews in the Middle East.
  3. Racial profiling – Profiling of minorities, and stereotyping people based on race or ethnicity.
  4. 1st vs 2nd World – Cold War Era division (Soviet Union versus United States, 1947-1991) “us” versus “them” mentality.  
  5. Management vs workers – The perception of employees of a company that management is a separate out-group, with a different set of goals and agendas.
  6. Gender stereotypingGender stereotypes between men and women; this applies to assumptions about any gender category.
  7. Sports fanatics – Group allegiance to sports teams, and conflicts that can arise between fan groups from different teams.
  8. Educational elitism – Educational elitism, and the idea that one school’s group of students is less capable or less intelligent than another school’s group of students based primarily on what school a person attends.
  9. Gaming rivalries – One group of people interested in a specific hobby or genre of game (dungeons and dragons, a popular RPG game, etc.) who are biased against another group who are interested in a rival genre.
  10. Parent group conflicts at schools – Parent groups at schools who participate in committees and meetings and the outgroup bias against parents who choose not to.

Case Studies

1. Political Polarization

This effect was especially apparent during the polarizing 2016 election of ex-United States president Donald Trump.

While the media has always been a pervasive force in American politics, never before in America have social media platforms played such a large role in directly connecting candidates and elected officials to American citizens.

This allowed for like-minded supporters of Trumpian politics to form strong groups, and, conversely, anti-trump liberals to form equally strong separate groups.

Lennon (2018) in an ethnographic study, that involved interviewing multiple Trump supporters from all walks of life, sought to shed light on the in-group/out-group polarization that was occurring (and still continues today). He states:

“We often enlist the microlens of ethnography to iden- tify the continuity of things that may otherwise seem inconsistent—to “make sense” of those whom we im- pulsively otherize. While this analytical approach is not without its merits, our present political moment demands that we don’t simply explain away contradic- tions or search for continuity in these ways—that we instead explore the depths and reach of contradictions and the ubiquity of inconsistency”(p. 425).

His search led him to believe that there were many contradictory opinions amongst Trump supporters and that what may seem like one massive, like-minded ingroup, contained many inconsistencies and diverse viewpoints.

See also: Political Socialization

2. Profiling and Stereotyping

Profiling is a form of discrimination and prejudice that is based on race, ethnicity, or nationality.

It often involves targeting individuals by falsely assuming that they are involved in some kind of criminal act, or should be treated with suspicion. This can manifest itself in society in a number of ways.

A simple example would be being stopped by a police officer without provocation, being questioned in a public place and falsely accused of something, or simply being treated differently because of your appearance.

Lever (2015) asserts:

“Pre-emptive racial profiling is controversial both because it is pre-emptive – no known illegal act has yet been committed – and because of the racial component in the decision to intervene. As no known crime has been committed, pre-emptive police tactics, such as ‘stop and search’ or ‘stop and frisk’ raise the natural concern that unless the acts are limited in number and carefully described, police efforts to prevent crime will undermine the principle that people should be able to get on with their lives without explaining themselves to political authorities, if they are not evidently a threat to the rights and liberties of others”(pp. 3-4).

3. Sporting Team Allegiance

Group allegiance to sports teams, and conflicts that can arise between fan groups from different teams.

The idea that someone can be so passionate about a sport’s team, that they would resort to violence or other forms of harassment against another group of people who like a different team seems hard to imagine.

However, this isn’t the case in many countries; sports and the allegiance to one’s team can be a lifelong ingroup, and in many cases (for example, South American football/soccer, UK football/soccer, American football fans) an extremely strong bond can exist between fans.

According to researchers Nepomuceno et al. (2022) hooliganism, or violent groups of sports fanatics from different parts of the UK and Europe, have increased, as has their rowdy public antics.

He claims that:

“since the 60s, football (known as soccer in the United States) violence has been an increasing concern for many European countries, recently stated by many reports on the escalating number of football-related offenses, arrests, and the propensity to the unruly behavior of young people” (p. 1).

He explains that it is not only alcohol that fuels the anarchy seen at major sporting events, but “the rivalry of fans of different sports is a vector for violent behavior” (p. 2).


Allport, G. W. (1954). The nature of prejudice. Reading, MA: Addison-Wesley. 

Castano, E., & Yzerbyt, V. Y. (1998). The highs and lows of group homogeneity. Behavioural Processes42(2–3), 219–238. https://doi.org/10.1016/s0376-6357(97)00078-8

Leffler, M. P., & Borstelmann, T. (1994). Origins of the Cold War: An International History. The US, the Cold War, and the Color Line, 317–328.

Lennon, M. (2018). Revisiting “the repugnant other” in the era of Trump. HAU: Journal of Ethnographic Theory8(3), 439–454. https://doi.org/10.1086/700979

Lever, A. (2015). Race and Racial Profiling. SSRN Electronic Journal. https://doi.org/10.2139/ssrn.2675633

Nepomuceno, T. C. C., de Carvalho, V. D. H., Silva, L. C. E., de Moura, J. A., & Costa, A. P. C. S. (2022). Exploring the Bedouin Syndrome in the Football Fan Culture: Addressing the Hooliganism Phenomena through Networks of Violent Behavior. International Journal of Environmental Research and Public Health19(15), 9711. https://doi.org/10.3390/ijerph19159711

Pettigrew, T. F. (2011). Intergroup prejudice: Its causes and cures. Actualidades En Psicología22(109), 115. https://doi.org/10.15517/ap.v22i109.18

Simon, B. (1992). The Perception of Ingroup and Outgroup Homogeneity: Reintroducing the Intergroup Context. European Review of Social Psychology3(1), 1 -30. https://doi.org/10.1080/14792779243000005


Gregory Paul C. (MA)

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Gregory Paul C. is a licensed social studies educator, and has been teaching the social sciences in some capacity for 13 years. He currently works at university in an international liberal arts department teaching cross-cultural studies in the Chuugoku Region of Japan. Additionally, he manages semester study abroad programs for Japanese students, and prepares them for the challenges they may face living in various countries short term.

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This article was peer-reviewed and edited by Chris Drew (PhD). The review process on Helpful Professor involves having a PhD level expert fact check, edit, and contribute to articles. Reviewers ensure all content reflects expert academic consensus and is backed up with reference to academic studies. Dr. Drew has published over 20 academic articles in scholarly journals. He is the former editor of the Journal of Learning Development in Higher Education and holds a PhD in Education from ACU.

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