PARENTS DESCRIPTIONS OF OBJECTS - POTENTIAL DATA FOR CHILDRENS INFERENCES ABOUT CATEGORY PRINCIPLES

In generalizing from an individual object, humans expect some features of the object (e.g., a dog's fur or heart), but not others (e.g., the dog's collar or owner), to be present in other category members. Little is known about how people come to make such distinctions among properties, or about the relative influence of a priori constraints versus knowledge gained through experience. This research begins to work out these relative effects by focusing on parents' speech as a source of information for children in identifying valid inferences. Parents were given a set of pictures and asked to teach their 2- to 4-year-old children about categories at different hierarchical levels: basic (e.g., porcupine), superordinate (e.g., vehicle), and subordinate (e.g., monkey wrench) levels. Object descriptions differed at the three levels. Parents mentioned perceptual features and parts more often when discussing basic and subordinate categories, while they related more abstract functions when discussing superordinate categories. These differences could help children to pick out generalizable properties, since parents are emphasizing the properties that are typical of the category. Parents also may help children learn about the asymmetrical way that inferences are made within hierarchies, by anchoring general statements ("machines do work for us") with examples of how these properties would apply at more specific levels ("lawnmowers do work outside, mixers do work in the kitchen..."). The results are discussed in terms of possible ways in which children may use parents' descriptions as a source of data for their developing inferential abilities. © 1990.