APA Dictionary of Psychology

the theory that people’s default (set) tendency when making judgments about a target is to assimilate contextual elements into those judgments but that, with contrast effects occurring under relatively deliberative conditions, people actively attempt to partial out (reset) the contextual influence and instead inadvertently partial out elements of the target itself. Because resetting requires substantial cognitive effort, contrast effects are considered unlikely to occur under nondeliberative conditions. See also assimilation; flexible correction model; inclusion/exclusion model. [proposed by U.S. psychologist Leonard L. Martin and his colleagues]