IntelligenceChapter 9

What is intelligence?

How can it be measured?

Where does it come from?

What is Intelligence?

Some definitions Binet defined intelligence as an individual’s capacity to:

Find and maintain a definite direction or purpose Adjust strategy as necessary to achieve that purpose Evaluate or criticize that strategy so adjustments could be

made Wechsler

The aggregate or global capacity of an individual to act purposefully, think rationally, and deal effectively with the environment

Kaplan and Saccuzzo General potential independent of prior learning

g

VerbalReasoning

QuantitativeReasoning

LogicalReasoning

Spearman’s Theory of General Mental Ability

Cattel & Horn’s Theory of Intelligence

VerbalReasoning

QuantitativeReasoning

Abstract VisualReasoning

CrystallizedAbilities

FluidAbilities

g

Vocabulary test

Comprehension test

Absurdities test

Verbal relations test

Quantitative test

Number series test

Equation building test

Pattern analysis test

Copying test

Matrices test

Paper folding & cutting test

Sternberg’s Triarchic Theory

Gardner’s Multiple Intelligences

Logical-mathematical Linguistic Musical Spatial Bodily-kinesthetic Interpersonal Intrapersonal Naturalist

History of Intelligence Testing

First intelligence tests were devised by Francis Galton

In 1905, Binet developed test to measure child’s mental age

Lewis Terman revised the Binet scale to produce the Stanford-Binet (introduced IQ)

Weschler (1939) published improved measure for adults (introduced deviation IQ)

Intelligence Testing Today Intelligence tests contain diverse mix of questions

assessing abstract reasoning

Use modern deviation IQ scores normed for age

Typically M=100 SD=15

IQ scores vary across testings but intelligence tests have high reliability

Intelligence tests have demonstrated “limited” validity IQ tests are not widely used in non-Western cultures

Where Does Intelligence Come From? Nature (Hereditary)

Twin studies Adopted children Heritability ratios

Nurture (Environment) Adoption studies Environmental deprivation Environmental enrichment Generational increases

Interaction Model Intelligence influence by both factors Heredity and environment also interact Reaction range model

Cultural Differences in IQ Scores Average IQ scores for large minorities is somewhat

lower than the average for whites

Jensen and others argue these differences result from heredity

Kamin’s rebuttal

Socioeconomic disadvantage

Cultural test bias Mercer (1975) IQ argued tests measure ability and

assimilation into mainstream culture

Not much empirical evidence that this is a problem