Intelligence Assessing Intelligence Assessing Intelligence Modern Tests of

Intelligence Assessing Intelligence

Assessing Intelligence § Modern Tests of Mental Abilities § Aptitude Test § a test designed to predict a person’s future performance § aptitude is the capacity to learn § Achievement Test § a test designed to assess what a person has learned

Assessing Intelligence § Wechsler Adult Intelligence Scale (WAIS) § most widely used intelligence test § subtests § verbal § performance (nonverbal)

Assessing Intelligence: Sample Items from the WAIS VERBAL PERFORMANCE General Information Similarities Arithmetic Reasoning Vocabulary Comprehension Digit Span Picture Completion Picture Arrangement Block Design Object Assembly Digit-Symbol Substitution From Thorndike and Hagen, 1977

Assessing Intelligence § Principles of Test Construction § Standardization § defining meaningful scores by comparison with the performance of a pre-tested “standardization group” § Normal Curve § the symmetrical bell-shaped curve that describes the distribution of many physical and psychological attributes § most scores fall near the average, and fewer scores lie near the extremes

The Normal Curve

Assessing Intelligence • The Flynn Effect – Tests are often restandardized to keep the average score near 100 – Intelligence test performance has been improving • The average person’s intelligence test score 80 years ago by today’s standards would be a 76 – Causes are unknown

Assessing Intelligence § Reliability § the extent to which a test yields consistent results § assessed by consistency of scores on: § Test/retest § Split-half

Assessing Intelligence § Validity § the extent to which a test measures or predicts what it is supposed to § Content Validity § Does the test measure what it is supposed to measure? § ex: driving test that samples driving tasks § Criterion § behavior (such as college grades) that a test (such as the SAT) is designed to predict § the measure used in defining whether the test has predictive validity

The Dynamics of Intelligence § Mental Retardation § a condition of limited mental ability § indicated by an intelligence score below 70 § produces difficulty in adapting to the demands of life § varies from mild to profound § Down Syndrome § retardation and associated physical disorders caused by an extra chromosome in one’s genetic makeup

The Dynamics of Intelligence