Abstract
The present study investigated the developmental trends of the hierarchical structure of natural categories. Children from first, third, and fifth grades of elementary level and undergraduate students served as subjects. They were asked to name the categorical objects in a particular context. The three experimental variables were: grade levels, categorical levels of a context, and structure of instances. As a measure of structuralization of the categorical hierarchy, the coordination of the categorical level in naming were analyzed. The results were as follows; 1) at the adult level, the systematic coordination of a categorical level was observed. By contrast, first graders persistently used very concrete names in spite of contextual changes. The third and fifth graders had a trend to relate the categorical level to the context, but not so orderly as the adults. 2) The coordination of naming had a developmental lag with the ability to judge the categorical relation, which interacted with the categorical level and the grades. According to the above findings, the developmental aspect of hierarchical structure of categories was discussed.
