Rules and exemplars in categorization, identification, and recognition.
Subjects learned to classify perceptual stimuli varying along continuous, separable dimensions into rule-described categories. The categories were designed to contrast the predictions of a selective-attention exemplar model and a simple rule-based model formalizing an economy-of-description view. Converging evidence about categorization strategies was obtained by also collecting identification and recognition data and by manipulating strategies via instructions. In free-strategy conditions, the exemplar model generally provided an accurate quantitative account of identification, categorization, and recognition performance, and it allowed for the interrelationship of these paradigms within a unified framework. Analyses of individual subject data also provided some evidence for the use of rules, but in general, the rules seemed to have a great deal in common with exemplar storage processes. Classification and recognition performance for subjects given explicit instructions to use specific rules contrasted dramatically with performance in the free-strategy conditions and could not be predicted by the exemplar model.
Nosofsky
R M
RM
Department of Psychology, Indiana University, Bloomington 47405.
Clark
S E
SE
Shin
H J
HJ
D000328:Adult; D001288:Attention; D004193:Discrimination Learning; D005556:Form Perception; D006801:Humans; D008568:Memory; D011939:Mental Recall; D009949:Orientation; D010364:Pattern Recognition, Visual; D012718:Set, Psychology; D014163:Transfer, Psychology