Group Effect

A type of bias (see “Bias”) that occurs when participants in a group setting such as a focus group (see “Focus Group”) adapt or change their responses in some way. For example, people sometimes change their responses to match or align with the majority opinion of the group instead of expressing their own opinion. Also referred to as “Groupthink.”


A type of cognitive bias (see “Bias, Cognitive”) that refers to a specific phenomenon that can occur in a group setting (see “Group Effect”) whereby the desire for group cohesion results in a failure of members to think independently and evaluate information objectively, ultimately leading to errors in decision-making. Groupthink has relevance for any media and market research that makes use of groups, such as focus groups (see “Focus Group”).