Piaget, in describing the sequence of classificatory development, describes class inclusion as composed of two processes; hierarchical classification and post-whole comparisons. In the experiment reported here, elementary school children, trained in the concept of sets in first grade mathematics were given a task where they were required to assess…

This study was designed to measure adult performance as related to age. Using methodology derived from information theory, information processing ability was measured with the individuals performing as a communication system. Fifty-five school teachers, ranging in age from 20 to 66, served as subjects. In four groups, the subjects judged the sizes…