History of Intelligence Tests AP Psychology

Intelligence The capacity to think and reason clearly, act purposefully and effectively in adapting to the environment and pursuing one’s goal.

Alfred Binet 19 th century France Laws requiring education for all children Government asked Binet and Theodore Simon to develop a test. Identify students who needed remedial help.

Contribution to Intelligence testing Assumption: Mental age: intellectual abilities grow year by year the chronological age that corresponds to the difficulty level of the questions a child can answer.

Binet’s beliefs Intelligence is determined mostly by environment children should be provided exercises to help them increase their mental abilities.

Lewis Terman (Stanford Professor) Adapted the Binet and Simon test for U.S. School- children. 1.standardized the test/one individual at a time 2.age-level norms New test: Stanford-Binet Intelligence Scale Test was designed for both children and adults.

Why did Intelligence test become popular in America? 1.Late 19 th century/early 20 th century…experienced large wave of immigrants. 2.Compulsory Laws were developing 3.WWI…military needed a way of assessing and classifying the new recruits.

Intelligence Quotient (IQ) IQ = Ex. A 10-year-old child who could answer questions suited to the average 11-year-old would have an IQ of 11/10 x 100=110 An 8-year-old who could answer only 6-year- old questions would have an IQ of 6/8 x 100= 75.

Disagreement within the field Lewis Terman: intelligence was largely determined by genetics. Reasonably fixed

Modern IQ tests THE ORIGINAL FORMAL IS NO LONGER USED. It has been modified to include…. Measure a very specific mathematical score based on the standard deviation.

Breakdown of IQ scores 70 (mentally inadequate) 85 (low intelligence) 100 (average) 110 (above average)IQ of 140 Mildly Gifted to 129 Moderately Gifted to 144 (1% of the world’s pop.) Highly Gifted to 159 Exceptionally Gifted to 179 Profoundly Gifted

Adult IQs of famous people Bobby Fischer (Chess Player)187 Galileo Galilei (Astronomer/Philosopher/Physicist) 185 Rene Descartes (Philosopher/Mathematician)180 Immanuel Kant (Philosopher)175 Charles Darwin (Naturalist)165 Wolfgang Amadeus Mozart (Composer)165 Albert Einstein (Physicist)160 George Eliot (Writer)160 Nicolaus Copernicus (Astronomer)160 Rembrandt van Rijn (Painter)155

Modern IQ Test David Wechsler Wechsler Adult Intelligence Scale (WAIS) Wechsler Intelligence Scale for Children (WISC) Wechsler Preschool and Primary Scale of Intelligence (WPPSI)

Wechsler’s IQ Tests Separate scores for verbal and nonverbal abilities Verbal: vocab., math, immediate memory span Performance: non verbal skills….block design etc. Individual tests

Sample questions from a modern IQ test Can be found on page 459. Try the “Do IT Yourself” activity.

Achievement vs. Aptitude Tests Achievement test= attempt to measure what the test-taker has accomplished. Aptitude tests= attempt to predict the test- taker’s future performance. Ex. College entrance exams like the American College Test (ACT)

What does the research tell us? Heredity and environment tend to interact to produce intelligence in individuals. The difference in average test scores could, most psychologists believe, be the result of environment.