Prior knowledge and exemplar encoding in children's concept acquisition.

Three experiments examined how children's domain knowledge and observation of exemplars interact during concept acquisition and how exposure to novel exemplars causes revision of such knowledge. In Experiments 1 (N = 126) and 2 (N = 64), children aged 4 to 10 years were shown exemplars of fictitious animal categories that were either unrelated to, or consistent with, their prior knowledge in 25% or 75% of presented exemplars. In Experiment 3, children (N = 290) saw fictitious animal, artifact, or unfamiliar social categories that were either consistent or inconsistent with their prior knowledge in 20%, 40%, 60%, or 80% of exemplars. In the test, children made judgments about the likely co-occurence of features. In all experiments, prior knowledge and exemplar observation independently influenced children's categorization judgments. Utilization of prior knowledge was consistent across age and domain, but 10-year-olds were more sensitive to observed feature covariation. Training with larger categories increased the impact of observed feature covariation and decreased reliance on prior knowledge.