The process of forming operator schemata was studied in three experiments. In each experiment a greater amount of predictive information in a stimulus item increased the chance of selecting the operator accurately.

Six experiments examined the problem-solving behavior of normal and mentally retarded (MR) children with a two-choice discrimination learning situation: the effects of stimulus similarity upon types of solutions utilized by MR children; the role of redundant cues in the discrimination learning of MR subjects with differing mental ages; the…