Evidence for rule-based processes in the inverse base-rate effect.
Three studies provide convergent evidence that the inverse base-rate effect (Medin & Edelson, 1988) is mediated by rule-based cognitive processes. Experiment 1 shows that, in contrast to adults, prior to the formal operational stage most children do not exhibit the inverse base-rate effect. Experiments 2 and 3 demonstrate that an adult sample is a mix of participants relying on associative processes who categorize according to the base-rate and participants relying on rule-based processes who exhibit a strong inverse base-rate effect. The distribution of the effect is bimodal, and removing participants independently classified as prone to rule-based processing effectively eliminates the inverse base-rate effect. The implications for current explanations of the inverse base-rate effect are discussed.
Winman
Anders
A
Department of Psychology, Uppsala University, Uppsala, Sweden. Anders.Winman@psyk.uu.se
Wennerholm
Pia
P
Juslin
Peter
P
Shanks
David R
DR
D000328:Adult; D002648:Child; D003071:Cognition; D006801:Humans; D011340:Problem Solving; D014163:Transfer, Psychology