Illusory Correlation

Illusory correlation is the perception of a relationship between two variables, typically two events or a group membership and a behavior, that does not actually exist or is weaker than perceived, arising because the association stands out or is more memorable than an accurate accounting of the actual co-occurrence would support. The psychologists Loren Chapman and Jean Chapman documented the effect in a series of studies beginning in 1967, finding that clinicians and lay participants alike reported seeing correlations between Rorschach inkblot responses and diagnostic categories that were not actually present in the data they were shown. The concept has been particularly influential in social psychology research on stereotype formation, where illusory correlation is used to explain how a distinctive but statistically rare behavior by a minority group member can become disproportionately associated with that group in observers' memory.