Formal thinking about correlation

Twenty-five adults were administered two tasks involving the data of 12,2X2 matrices. In the first, subjects were invited to make decisions on the basis of data which was presented as involving causal, one-way relationships. Four groups of subjects were distinguished in the level of their operational thinking. In task 2 the subjects were invited to make judgements on identical data, but presented as involving two-way noncausal relationships. Results showed changes in the level of thought: subjects employing concrete operations in task 1 regressed to lower levels of thought; subjects employing transitional formal thought in task 1 advanced to fully formal thought in task 2. It was concluded that the first task imposed a ceiling effect on the thought levels of the latter subjects. Results showed that the level of thought employed was a function of the frequency of the data in the cells of the matrices and that the emergence of illogical thought was related to task difficulty.