ABSTRACT
Few features of the secondary-school selection examination provoke more criticism and misunderstanding than intelligence tests. The main object of introducing intelligence tests was to eliminate vagaries of human judgement, and to provide an objective assessment of ability. Many group tests contain similar items requiring classifying, reasoning and grasping relations but using non-verbal material, either pictures or abstract diagrams. Most psychologists regard an individual test intelligence quotient (IQ) as giving a more reliable and representative all-round survey of a child's intellectual powers, although there is no evidence that it is more predictive of ability to do grammar-school work than is the result of a group test. Quite early in the history of mental testing it was observed that children of gipsies, tinkers or canal boatmen, who received scarcely any schooling, obtained very low IQs on the Binet-Simon scale. This was interpreted to mean that the tests measured inborn ability only when children had had normal educational opportunities.
