Intelligence
Chapter 9
What is intelligence?
Where does it come from?
How can it be measured?
What is Intelligence?
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Some definitions
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Binet defined intelligence as an individual’s capacity to:
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Wechsler
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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
The aggregate or global capacity of an individual to act
purposefully, think rationally, and deal effectively with the
environment
Kaplan and Saccuzzo
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General potential independent of prior learning
Spearman’s Theory of General
Mental Ability
g
Verbal
Reasoning
Quantitative
Reasoning
Logical
Reasoning
Cattel & Horn’s Theory of Intelligence
g
Fluid
Abilities
Crystallized
Abilities
Verbal
Reasoning
Vocabulary test
Comprehension test
Absurdities test
Verbal relations test
Quantitative
Reasoning
Quantitative test
Number series test
Equation building test
Abstract Visual
Reasoning
Pattern analysis test
Copying test
Matrices test
Paper folding & cutting test
Sternberg’s Triarchic Theory
Gardner’s Multiple Intelligences
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Logical-mathematical
Linguistic
Musical
Spatial
Bodily-kinesthetic
Interpersonal
Intrapersonal
Naturalist
History of Intelligence Testing
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First intelligence tests were devised by Francis
Galton
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In 1905, Binet developed test to measure child’s
mental age
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Lewis Terman revised the Binet scale to
produce the Stanford-Binet (introduced IQ)
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Weschler (1939) published improved measure
for adults (introduced deviation IQ)
Intelligence Testing Today
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Intelligence tests contain diverse mix of questions
assessing abstract reasoning
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Use modern deviation IQ scores normed for age
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Typically M=100 SD=15
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IQ scores vary across testings but intelligence tests
have high reliability
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Intelligence tests have demonstrated “limited” validity
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IQ tests are not widely used in non-Western cultures
Where Does Intelligence Come From?
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Nature (Hereditary)
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Twin studies
Adopted children
Heritability ratios
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Nurture (Environment)
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Adoption studies
Environmental deprivation
Environmental enrichment
Generational increases
Interaction Model
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Intelligence influence by both factors
Heredity and environment also interact
Reaction range model
Cultural Differences in IQ Scores
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Average IQ scores for large minorities is somewhat
lower than the average for whites
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Jensen and others argue these differences result from
heredity
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Kamin’s rebuttal
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Socioeconomic disadvantage
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Cultural test bias
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Mercer (1975) IQ argued tests measure ability and
assimilation into mainstream culture
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Not much empirical evidence that this is a problem