1. Unit 6: Testing and Individual Differences
Module 32:
Assessing Intelligence

2. Assessing Intelligence
Intelligence is whatever an intelligence test meaures.
Intelligence Test: A method for assessing an individual’s mental aptitudes and comparing them with those of others, using scores.

3. Origins of Intelligence Testing
When laws for mandatory schooling began, testing was needed to separate those who needed “extra” attention and those who didn’t.
Testing was a way to minimize bias.
Alfred Binet: French psychologist who invented the first practical intelligence test to identify students who needed special help.

4. Origins of Intelligence Testing
Alfred Binet (below) and Theodore Simon developed questions that would predict children’s future progress in the Paris school system.
The Binet-Simon Scale measured a child’s mental age.

5. Origins of Intelligence Testing
Mental age: the age that most typically corresponds to a given level of performance.
A child who does as well as the average 8 year old has a mental age of 8.
A child can have a mental age smaller or larger than their chronological age.
Mental age of 8, chronological age of 6.

6. Origins of Intelligence Testing
Lewis Terman: Stanford professor who adapted Binet’s test for American school children.
The Stanford-Binet test is widely used today.

7. Origins of Intelligence Testing
William Stern: German psychologist who created the IQ.
Mental age
Chronological age
IQ =
x 100
A child with a mental age of 10 and a chronological age of 8:
Thus the average IQ is 100. 10 8
IQ =
x 100
= 125

8. Origins of Intelligence Testing
Terman believed in eugenics and testing was a way to curb the production of “feeble-minded” children.
Eugenics: 19th century movement that proposed measuring human traits and using the results to encourage only smart and fit people to reproduce.

9. Origins of Intelligence Testing
The U.S. government curbed immigration using IQ tests to stop those less intelligent from coming to America.
Thus one major drawback of testing is labeling children as inferior, slow, or unfit.
Prejudice can come from not just skin color, but from intelligence.

10. Modern Tests of Intelligence
Aptitude: the capacity to learn.
Aptitude tests: a test designed to predict a person’s future performance.
Ex. ACT (college readiness), driver’s test (driving ability), Selective enrollment test (HS), etc.
Scores on the SAT and IQ tests has a correlation.

11. SAT and IQ Correlation

12. Modern Tests of Intelligence
Achievement tests: a test designed to assess what a person has learned.
Ex. Tests, quizzes, AP Exam, etc.
Wechsler Adult Intelligence Scale (WAIS): most widely used intelligence test today.
Wechsler Intelligence Scale for Children (WISC): intelligence test for children.

13. Test Construction
Psychological tests must meet 3 criteria to be accepted: standardized, reliable, and valid.
Standardization: give test to a representative sample AND assure that the test is both administered and scored the same for everyone.
It defines what the score you get means!

14. Test Construction
Normal Curve: a bell shaped curve in which most scores fall near the average and fewer scores are at the extremes.

15. Test Construction
Reliability: the extent to which a test yields consistent results.
Repeat the test to see if, over time, you get the same results.
Methods of measurement include test-retest(use same test), split-half (odd-even halves), and alternate form(different forms of same test).

16. Test Construction
Validity: what the test is supposed to measure or predict.
Content Validity: measures a particular behavior or trait.
Driving test measures driving ability.
Predictive Validity: able to predict future achievement.
ACT must be able to predict college readiness or its not valid.

17. Extremes of Intelligence
No real predictors for intelligence among babies up to 3 years of age.
Beginning at age 4, intelligence tests begin predicting adult scores.
At age 7, intelligence scores stabilize.

18. Extremes of Intelligence
A valid test divides people into two extreme groups: mentally retarded (IQ<70) and gifted (IQ>135).

19. Extremes of Intelligence
Mental retardation: low test score and difficulty living independently.

20. Extremes of Intelligence
Gifted children makes up 3 – 5% of the population.
They are sometimes more isolated, introverted, and in their own worlds, but most thrive and are successful.
High scorers tend to be healthy, well adjusted, and academically successful.