The quest for determining the degree of learning difficulty associated with different types of categories has been instrumental in our understanding of human categorization behavior and, more broadly, human generalization. For instance, we now know that the topological nature of the dimensions (e.g., whether these are integral or separable) that…

The findings of Shepard, Hovland, and Jenkins (1961) on the relative ease of learning 6 elemental types of 2-way classifications have been deeply influential 2 times over: 1st, as a rebuke to pure stimulus generalization accounts, and again as the leading benchmark for evaluating formal models of human category learning. The litmus test for models…

This paper presents the empirical basis for the phenomena known as stimulus overselectivity. Stimulus overselectivity involves responding on the basis of a restricted range of elements or features that are discriminative for reinforcement. The manner in which such a response pattern impedes the skill acquisition in children is identified. A…

The role of variation as a determinant of infant categorical responding was investigated in three studies of infants 7 to 7 1/2 months of age. Sixty-three infants, divided into groups of 21 each, were habituated to color slide poses of either one, two, or six different adult female faces. Their responses to a novel pose of a familiar face and a…

TWO EXPERIMENTS WERE CONDUCTED IN ORDER TO OBTAIN A MATHEMATICAL DESCRIPTION OF THE PERCEPTUAL PROCESS BY WHICH NORMAL AND MENTALLY RETARDED SUBJECTS SYNTHESIZE STIMULUS CUES IN PERCEPTUAL IDENTIFICATION. THE INITIAL STUDY EMPLOYED 50 COLLEGE STUDENTS, 34 GRADE SCHOOL STUDENTS, AND 24 MENTALLY RETARDED CHILDREN (AGES 9-16) AS SUBJECTS. THE…

Accounts of learning and generalization typically focus on factors related to lasting changes in representation (i.e., long-term memory). The authors present evidence that shorter term effects also play a critical role in determining performance and that these recency effects can be subdivided into perceptual and decisional components.…

Three studies explored whether children's tendency to extend object names on the basis of sameness of shape (shape bias) is specific to naming. Findings indicated that 2- and 3-year-olds showed shape bias both when asked to extend a novel name and when asked to select an object of the same kind as a target object; 3-year-olds also showed shape…

Looking times of 36 children were recorded during subject-controlled presentation of slides in order to determine whether the existence of simple categories in 3-year-olds can be inferred from habituation data, and to determine any sex differences in conceptual generalization of habituation. Habituation was demonstrated over repeated presentation…

Five experiments were performed in which nursery school children were taught to identify persons, animals, or objects in pictures that took the nominative, objective, or locative case in sentences about the pictures. Inferences are made about categories in children's thinking including animate, and actor and agent. (CTM)