Intelligence Francis Galton · Forefather of intelligence tests Believed there were differences in intelligence - The ability to respond to the large range of information available to the senses e.g. discriminate between hot and cold; reaction time; keenness of sight and hearing Alfred Binet · In 1904 French government commissioned Binet to devise techniques to identify children who needed extra/alternative schooling. · Developed (with Theodore Simon) a series of short tasks (easy to hard): - Following a lighted match with your eyes (easy) - Naming parts of the body; repeating sentences (medium) - Reproduce a drawing; recall digit strings (difficult) · Introduced the concept of age - How well is child doing compared to his/her age group Lewis Terman · Terman uses the Binet-Simon test on Californian school-children - Made revisions: Stanford-Binet test - Highlighted the need for standardised tests based on representative samples Robert Yerkes · When the US entered WW1 (1917) he was asked to consider how psychology could help the war effort · They wanted to quickly classify recruits to perform suitable roles · Army alpha test - Language and knowledge-oriented tasks - Use synonyms and antonyms - Follow oral directions - Practical judgement (e.g. correct solution to a presented scenario) · Army beta test - Less language oriented - Maze task - Cube analysis (counting cubes) - Matching numbers to symbols - Geometric construction · The tests interested broader society, not very helpful during WW1 as war ended Charles Spearman · Spearman collected data on a range of cognitive tests · Noted a positive manifold - Test performance across a range of domains showed positive correlations · Used factor analysis on these data - Discovered a consistent general factor (Spearman's g) - Believed that g reflected a kind of mental energy; a deeper fundamental mechanism - Also posited specific factors - Two-factor model: g and specific factor
David Wechsler · US based; Columbia University . In the 1930s he set about developing a standardised test that would capture general and specific intelligence. · Work led to a standard measure in wide use today: Wechsler Adult Intelligence Scale (WAIS) - Task domains include: arithmetic; block design; comprehension; digit span; information; object assembly; picture arrangement; picture completion; vocabulary · Identified a standard deviation of IQ across the nation, 100 = mean of population · Example of test - Visual Spatial tests - Digital Recall - Matrix task - Inspection times Structure Models: Spearman · G factor and specific factor · G factor = general ability Structure Models: Carroll's 3 strata model · General view is that G factor sits above all subdomains . Within these specific domains there is a further break down of more narrow abilities Structure Models: Howard Gardner · Theory of Multiple Intelligences - linguistic; spatial; musical; bodily kinaesthetic; interpersonal; intrapersonal · Main criticisms - No tests of his model of intelligence exist - Does not take into account the positive manifold; g factor - He largely fails to respond to criticism Does Intelligence Matter?