One hundred and sixty subjects from five age levels ranging from 3 to 20 years compared photographs of dogs (e.g., two different Great Danes or a Great Dane and a Doberman pinscher) and judged whether they were similar or different. (Author/MP)

Investigated the development of classificatory organization. Two experiments examined age differences in children's spontaneous extensions of a classification and a third examined children's extensions under hypothesis-testing instructions. (JMB)

Picture-grouping and word-association tasks were used to evaluate the hypothesis that paradigmatic (same form class) word associates are not always categorical and may be a function of the child's understanding of interactive and categorical relations. (SB)

Two studies with 3-, 4-, and 5-year-olds examined whether young children can differentiate expertise in the minds of others. Findings indicated that all children could correctly attribute observable knowledge to familiar experts, such as a car mechanic. Preschoolers had difficulty making attribution of knowledge of scientific principles to…

Expectations concerning form and color in object label referencing of 80 children of 2-3 years were examined in 2 studies. Findings show that children as young as 2 expect form similarity to be a better guide than color similarity to the extension of object labels. (RJC)

The ability of six-month-old infants to remember a functional category acquired in a specific context was assessed in three experiments. Findings revealed that at six months, information about the place where categories are constructed is prerequisite for retrieval of a category concept from long-term memory. (GLR)

Addresses Nelson's commentary on Ward, Vela, and Hass' study of children's category learning (both of which are in this issue). Discusses the issue of whether a holistic processing view provides a better account of children's learning than does an analytical view. (PCB)

Two experiments examined 4- to 5-year-olds' acquisition of family-resemblance categories for fictitious animals. Results showed that children who performed theory-guided learning were more successful at making feature/category associations than children who performed similarity-guided learning and categorized attributes significantly better than…

Four experiments investigated 3-year-olds' understanding of the differential importance of shape for categorizing solid objects. Found that they categorized rigid and deformable objects differently in a non-naming task and knew that material was important for deformable items and shape for rigid items. In two naming tasks, they generalized names…

Two experiments tested a model of young children's induction that specified contributions of linguistic labels and perceptual similarity to children's induction. Results support model predictions and point to a developmental shift, from treating linguistic labels as an attribute contributing to similarity to treating them as markers of a common…

The ability to perform induction appears early; however, underlying mechanisms remain unclear. Some argue that early induction is category based, whereas others suggest that early induction is similarity based. Category- and similarity-based induction should result in different memory traces and thus in different memory accuracy. Performing…

One hundred 18-month-olds were tested using sequential touching and following 4 different priming contexts using sets of toys that could be simultaneously categorized at either the basic or global level. An exact expression of the expected mean sequence length for arbitrary categories was derived as a function of the number of touches made, and a…

Young children usually prefer to classify objects on the basis of shape rather than color. The present study explored this phenomenon with a stimulus matching test and a component selection test. (ST)

In two studies, preschoolers and second graders were tested on their understanding that members of a category have similar parts. Children in both studies drew many inferences concerning the internal structure of objects in basic-level categories. Suggests that preschool children assume that basic-level categories share internal parts. (RJC)