Performance on Measurement and Pseudomeasurement Tasks by Five‐ to Seven‐year‐old Children

Subjects trained by a non‐verbal reinforcement method to select the longer one of a pair of sticks were given two genuine measurement (G) and two pseudomeasurement (P) tests. The first P‐test involved the use of two measuring sticks, clearly different in length, and the second test addition or subtraction of a piece of the measuring stick between measurements. A single factor seemed to generate much of the performance in all four tests, suggesting that, since the P‐tasks had to be solved by means of non‐transitive inferences, the G‐tasks were solved in the same way. It is concluded that non‐verbal reinforcement methods may not yield a valid diagnosis of transitivity.