Psych test - a standardized measure of a sample of persons behaviour. Aptitude tests - designed to predict your ability to learn a new skill. Intelligence - mental potential to learn from experience, to solve problems, use knowledge to adapt to new situations. Galton (1884): iq was reflected by superior sensory acuity and physical attributes. Binet (1905): iq was reflected through mental abilities. Stern: intelligence quotient (iq) (mental age/ chronological age) * 100. Take a person"s iq score + compare it to the scores of others in the same age group. Mean performance for a certain age group is set at 100. You then see how far a person"s score deviates from that average. Mental age - refers to a kid"s performance on a test expressed in years compared to typical performance at that age. Analytical iq - ability to reason, traditionally measured on iq tests, kind of intelligence needed to do well academically.