In-group bias

In-group bias, also known as in-group favoritism, is a cognitive bias where individuals tend to favor, support, and give preferential treatment to members of their own group over those in other groups. This bias is a fundamental aspect of human social interaction where familiar things and familiarity with the in-group lead to implicit positive associations, often regardless of objective evidence or actual differences among groups.

How it works

In-group bias operates through social categorization, where the brain simplifies the world by sorting people into groups based on perceived similarities such as ethnicity, nationality, or shared interests. Once categorization occurs, psychological mechanisms such as social identity theory suggest that individuals derive part of their self-esteem from their group memberships, thus fostering favoritism towards their group. This process often involves positive stereotyping of in-group members and a corresponding negative bias against out-group members, sometimes without any rational basis.

Examples

  • Sports enthusiasts supporting their home team even when objectively it might not be the better team.
  • Hiring practices within organizations where managers tend to prefer candidates who share their same cultural or educational background.
  • Nationalism, where citizens of a country may view their own nation in a favorable light while holding prejudices against foreigners.

Consequences

The consequences of in-group bias can be seen in increased group cohesion and loyalty, but also in intergroup conflict and discrimination. It can lead to exclusionary practices, lack of diversity in decision-making, and perpetuation of inequality as those outside the favored group are overlooked or negatively stereotyped.

Counteracting

Counteracting in-group bias involves promoting awareness and understanding of the bias, encouraging inter-group contact and cooperation, and fostering an environment that values diversity and inclusion. Techniques such as perspective-taking, empathy training, and promoting a superordinate identity that includes both in-group and out-group members can help mitigate bias.

Critiques

While the concept of in-group bias is well-documented, critiques often focus on its potential oversimplification of complex social dynamics. Some argue that it fails to adequately explain how individuals may not exhibit these biases in certain circumstances, or how out-group favoritism can also occur. Additionally, cultural and contextual factors can moderate the expression of in-group bias, suggesting a need for more nuanced understanding.

Also known as

In-group favoritism
Intergroup bias
Group bias

Relevant Research

  • Social Identity and Intergroup Discrimination

    Henri Tajfel, John C. Turner (1986)

    Annual Review of Psychology

  • In-group favoritism and self-esteem

    Marilynn B. Brewer (1979)

    Psychological Science

Case Studies

Real-world examples showing how In-group bias manifests in practice

Engineers First: When the Team Becomes the Target Customer
A real-world example of In-group bias in action

Context

A mid-stage SaaS company built by engineers was scaling from 40 to 120 employees while chasing product-market fit. Leadership relied heavily on engineering-led decisions because the founding team came from deep technical backgrounds and trusted their own judgments about what customers needed.

Situation

The product roadmap began prioritizing features that made internal development and deployment easier (SDKs, internal dashboards, CI integrations) rather than features requested by the largest customer segment (simpler onboarding flows and analytics for non-technical managers). Product decisions were often made in engineering-dominated meetings where engineers were the loudest voices.

The Bias in Action

Team members consistently evaluated feature requests through the lens of what would benefit engineers, implicitly treating engineers as the prototypical user. When non-technical customers raised pain points in support tickets or customer calls, those items were deprioritized because 'no engineer would use that.' Hiring for the product team also favored candidates from the founding engineers' networks, reinforcing the engineering-centric perspective. Over months, customer feedback from business users was dismissed as outlier noise rather than input requiring prioritized fixes.

Outcome

Within six months the company saw stagnating adoption among its largest customer segment while internal tools were rolled out rapidly. Customer-support tickets for onboarding issues rose 35%, and churn among small-to-medium business customers increased by 12% quarter-over-quarter. The engineering team celebrated faster deploys and cleaner code, while revenue growth slipped below projections.

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In-group bias - The Bias Codex