Development of multiple dimension use in form classification.

The use of multiple form dimensions in pattern classification was studied with adults and children in grades 2 and 5. Each subject sorted 30 8-sided random polygons first into 2, then into 3, and finally into 4 groups and repeated the procedure 1 week later. A series of discriminant analyses, using 9 physical form characteristics as predictors, was used to answer several developmental questions. Reliability of classification, number and saliency of features selected, and accuracy with which they were used all implied continuous development of perceptual skills. Multiple feature use in classification was evidenced at all age levels.