INTELLIGENCE AND PSYCHOLOGICAL TESTING

KEY CONCEPTS IN PSYCHOLOGICAL TESTING Psychological test: a standardized measure of a sample of a person’s behavior Measure individual differences that exist among people in abilities, aptitudes, interests, and aspects of personality

MENTAL ABILITY TESTS Most common Include intelligence tests: measure general mental ability---assess intellectual ability Aptitude tests: assess specific types of mental abilities Achievement tests: gauge a person’s mastery of knowledge and various subjects

PERSONALITY TESTS DEF: measure various aspects of personality, including motives, interests, values, and attitudes

STANDARDIZATION AND NORMS Standardization: refers to the uniform procedures used in the administration and scoring of a test Test norms: provide info about where a score on a psychological test ranks in relation to other scores on that test Percentile score: indicates the percentage of people who score at or below the score one has obtained

RELIABILITY Refers to the measurement consistency of a test Test-retest, split-half reliability Reliability estimates require computation of correlation coefficients: a numerical index of the degree of relationship btwn 2 variables

VALIDITY Refers to the ability of a test to measure what it was designed to measure Content validity: degree to which the content of a test is representative of the domain it’s supposed to cover Criterion-related validity: estimated by correlating subjects’ scores on a test with their scores on an independent criterion of the trait assessed by the test Construct validity: the extent to which there is evidence that a test measures a particular hypothetical construct

EVOLUTION OF INTELLIGENCE TESTING

GALTON’S STUDIES OF HEREDITARY GENIUS Sir Francis Galton Found that success and eminence ran in families Wrote Hereditary Genius in 1869 Coined the term nature vs. nurture Invented concepts of correlation and percentile test scores

BINET’S BREAKTHROUGH Alfred Binet asked to devise a test to identify mentally sub-normal children Worked with Theodore Simon The Binet-Simon scale expressed a child’s mental age: displays the mental ability typical of a child of a chronological age

TERMAN AND THE STANFORD-BINET Lewis Terman of Stanford expanded and revised Binet’s test 1916: Stanford-Binet Intelligence Scale Included intelligence quotient (IQ): a child’s mental age divided by chronological age, multiplied by 100

WECHSLER’S INNOVATIONS David Wechsler wanted a test for adults Wechsler Adult Intelligence Scale (WAIS) published in 1939 Less dependent on verbal ability Discarded IQ in favor of normal distribution

INTELLIGENCE TESTING TODAY 2 categories: Individual tests and group tests Individuals are time consuming and costly Schools use Otis- Lennon School Ability Test and Lorge- Thorndike Intelligence Test

BASIC QUESTIONS ABOUT INTELLIGENCE TESTING

WHAT KINDS OF QUESTIONS? Fairly diverse Information, vocabulary, demonstrate memory Manipulate words, numbers, and images through abstract reasoning

WHAT DO MODERN IQ SCORES MEAN? Normal distribution: a symmetric, bell-shaped curve that represents the pattern in which many characteristics are dispersed in the population Scores translated into deviation IQ scores: locate subjects precisely within the normal distribution, using the standard deviation as the unit of measurement Scores indicate exactly where you fall in the normal distribution of intelligence

DO INTELLIGENCE TESTS MEASURE POTENTIAL OR KNOWLEDGE? Intelligence tests are intended to measure intellectual potential Reality: they measure both

DO INTELLIGENCE TESTS HAVE ADEQUATE RELIABILITY? Correlations range into the.90s They are reliable, but represent a sample Test anxiety can shift scores