Assesses preschoolers' and adults' relative ability to solve classification problems in which a similarity criterion is the only criterion appropriate for solution. Also investigates effects of the salience of individual dimensions on solution-relevant similarity classifications. (AS)

In four experiments, younger children and adults showed greater perceptual sensitivity and more extensive conceptual labeling for difference relations than for identity relations. Younger and older children demonstrated consistent dimensional selectivity in tasks involving free classification and the estimation of differences. (Author/BG)

Investigates the effects of predisposed and distinctiveness-based salience on children's classifications in 96 preschoolers and fifth graders given a classification task designed to reflect a developmental shift from integral to separable perception. (Author/MP)

Two experiments investigated perceptual primacy of dimensional and similarity relations in stimulus classifications of younger and older subjects. Results support a differential-sensitivity view of perceptual development which asserts that individuals at all ages primarily perceive and use separate relations. (RWB)