History of History of Intelligence Intelligence

TestsTestsPsychologyPsychology

IntelligenceIntelligence• The capacity to think and reason

clearly, act purposefully and effectively in adapting to the environment and pursuing one’s goal.

Alfred BinetAlfred Binet

• 19th 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 Contribution to Intelligence testing-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 beliefsBinet’s beliefs• Intelligence is determined mostly by

environment• children should be provided

exercises to help them increase their mental abilities.

Disagreement within the Disagreement within the fieldfield

• Lewis Terman: intelligence was largely determined by genetics.

• Reasonably fixed• He revised the original Binet and

Simon test for use with American children.

• Stanford-Binet intelligence test (modern version is used today)

Why did Intelligence test Why did Intelligence test become popular in America?become popular in America?• 1.Late 19th century/early 20th

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)Intelligence Quotient (IQ)• Terman and William Stern• IQ= MA/CA x 100• Example: 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

Breakdown of IQ scoresBreakdown of IQ scores• 70 (mentally inadequate) • 85 (low intelligence)• 100 (average)• 110 (above average)• Mildly Gifted -- 115 to 129 • Moderately Gifted -- 130 to 144 • Highly Gifted -- 145 to 159 • Exceptionally Gifted -- 160 to 179 • Profoundly Gifted -- 180

•

Problems formulaProblems formula• Assumption that mental abilities increase

a little bit every year. This statement holds true only for children

• Original Formal does not work for adults

Ex. An avg. 20-year-old would have an IQ of 100…20/20 x 100

By age 40 her/his IQ would drop to 50 because her CA has doubled but the MA has stayed the same!

Wechsler intelligence scalesWechsler intelligence scales• David Wechsler • (modern IQ test)Developed three tests: children (WISC),

preschool(WPPSI), and adult (WAIS)• Separate scores for verbal and nonverbal

abilities

Achievement vs. Aptitude Achievement vs. Aptitude TestsTests

• 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 exam like the American College Test (ACT)

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