Devised by the psychologist John Raven, this is a non-verbal test of intelligence for children. The box comprises sets A, AB and B (each consisting of 12 cards with removable inserts) in a leather suitcase. In each item of this test the child is asked to find a rule connecting a set of figures, and to complete this set according to the rule. In this way the psychologist can test the speed at which logical rules are generated and solutions found, and also the number of elements that the child can keep track of (their span capacity). Standard and advanced progresive matrices tests are also used on adults. This set is from the Crichton Museum in Dumfries, Scotland.
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