Intelligence

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Defining Intelligent Behavior

• What is intelligence?

• Intelligence– the capacity to understand the world, think

rationally, and use resources effectively when faced with challenges

• Intelligence Tests– tests devised to identify a person’s level of

intelligence

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Measuring Intelligence

• Mental age– the average age of children taking the Binet test who

achieved the same score

• Chronological age– physical age

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Measuring Intelligence

IQ=MA x 100 CA

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Tests of IQ

• Stanford-Binet Test

• Wechsler Adult Intelligence Scale-III (WAIS-III)

• Wechsler Intelligence Scale for Children-III (WISC-III)

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Achievement and Aptitude Tests

• Achievement Test– a test meant to ascertain a person’s level of

knowledge in a given subject area

• Aptitude Test– a test designed to predict a person’s ability in a

particular area or line of work– SAT, ACT

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Reliability and Validity

• Reliability– the concept that tests measure consistently what

they are trying to measure

• Validity– the concept that tests actually measure what

they are supposed to measure

• Norms– standards of test performance

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Alternative Formulations of Intelligence

• G or G-factor– an early theory that assumed there was a general factor

for mental ability

• Fluid Intelligence• reflects reasoning, memory, and information

processing capabilities

• Crystallized Intelligence• information, skills, and strategies that people have

learned through experience

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Alternative Formulations of Intelligence

• Gardner’s Seven Intelligences:• Musical intelligence

• Bodily kinesthetic intelligence

• Logical-math intelligence

• Linguistic intelligence

• Spatial intelligence

• Interpersonal intelligence

• Intrapersonal intelligence

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Contemporary Approaches

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Variations in Intellectual Ability

• Mental Retardation– a significantly subaverage intellectual

functioning that occurs with related limitations in two or more of the adaptive skill areas

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Variations in Intellectual Ability

• mild retardation– IQ = 55-69

• moderate retardation– IQ = 40-54

• profound retardation– IQ below 25

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Variations in Intellectual Ability

• Causes of mental retardation– identifiable biological reason (e.g. Down’s

Syndrome)– familial retardation

• Care and Treatment– least restrictive environment– mainstreaming– full inclusion

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Variations in Intellectual Ability

• The Intellectually Gifted– two to four percent of the population who have

IQ scores greater than 130– social stereotypes of gifted people

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Individual Differences in Intelligence

• Are traditional IQ tests culturally biased?

• Are there racial differences in intelligence?

• To what degree is intelligence influenced by the environment and to what degree by heredity?

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The Relative Influence of Heredity and of Environment

• Culture-fair IQ test– a test that does not discriminate against

members of any minority group

• Heritability– a measure of the degree to which a

characteristic is related to genetic, inherited factors

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The Flynn Effect