Psychology 102: Intelligence & Intelligence Assessment Dr James Neill Centre for Applied Psychology University of Canberra 2009

Reading Gerrig et al. (Chapter 9): Intelligence and Intelligence Assessment

What is intelligence? History of intelligence testing Features of good or bad tests (psychometrics) Cultural and social background on intelligence test performance Intelligence, creativity and mental illness Overview

What is intelligence?

History of intelligence testing

Features of good or bad tests (psychometrics)

Cultural and social background on intelligence test performance

Intelligence, creativity and mental illness

What is intelligence?

What is cognition? The process and content of “knowing”, including thinking, remembering, and communicating.

Cognitive Psychology

Intelligence as an “individual difference” Intelligence and personality are the most ubiquitous individual differences (e.g., commonly measured) Individual differences = stable human psychological characteristics which vary between people

Abstract thinking ability (Terman, 1921) Capacity for knowledge and knowledge possessed (Henmon, 1921) Capacity to learn from experience (Dearborn, 1921) Many definitions of intelligence

"The capacity to acquire capacity." (Woodrow, 1921) Ability to adapt to the environment. (Colvin, cited in Sternberg, 1982) “ a general factor that runs through all types of performance." (Jensen) Many definitions of intelligence

"A global concept that involves an individual's ability to act purposefully, think rationally, and deal effectively with the environment." (Wechsler, 1958) Many definitions of intelligence

"ability to solve problems, or to create products, that are valued within one or more cultural settings ( Gardner, 1983/2003, p. x)" Many definitions of intelligence

" The global capacity to profit from experience and to go beyond given information about the environment” (Gerrig et al., 2008) Many definitions of intelligence

History of intelligence assessment

Differences are quantifiable Differences form a normal distribution Measured by objective tests Statistically determined by correlations Galton’s ideas of intelligence

Differences are quantifiable

Differences form a normal distribution

Measured by objective tests

Statistically determined by correlations

Galton’s controversially postulated Genetic superiority and inferiority Started Eugenics movement Galtonian view Galton’s ideas of intelligence

Galton’s controversially postulated

Genetic superiority and inferiority

Started Eugenics movement

Galtonian view

Alfred Binet & Théophile Simon Mental age (MA) Chronological age (CA) Lewis Terman Stanford-Binet Intelligence Scale Intelligence Quotient (IQ) The origins of intelligence testing

Alfred Binet & Théophile Simon

Mental age (MA)

Chronological age (CA)

Lewis Terman

Stanford-Binet Intelligence Scale

Intelligence Quotient (IQ)

Alfred Binet and his colleague Théodore Simon practiced a more modern form of intelligence testing by developing questions that would predict children’s future progress in the Paris school system. Alfred Binet

In the US, Terman adapted Binet’s test -> the Stanford-Binet Test. Terman used Stern’s formula for Intelligence Quotient (IQ): Assessing intelligence: Lewis Terman

In the US, Terman adapted Binet’s test -> the Stanford-Binet Test.

Terman used Stern’s formula for Intelligence Quotient (IQ):

Intelligence Quotient Stanford-Binet Intelligence Test Wechsler Intelligence Scales Verbal subtests Performance subtests WAIS -3, WISC-4, WPPSI - 3 IQ and IQ Tests

Intelligence Quotient

Stanford-Binet Intelligence Test

Wechsler Intelligence Scales

Verbal subtests

Performance subtests

WAIS -3, WISC-4, WPPSI - 3

Interpreting scores: The normal curve

Intelligence scores become stable after about seven years of age. In numerous studies, stability of intelligence scores have been determined (Angoff, 1988; Deary et al., 2004). Stability or Change?

Recent studies indicate some correlation (~ .40) between brain size and intelligence. As brain size decreases with age, scores on verbal intelligence tests also decrease. Is intelligence neurologically measurable?

Features of Formal Assessment of Intelligence

Use of specified procedures to evaluate abilities, behaviours, and personal qualities Referred to as the ‘measurement of individual difference' Psychological assessment: What is it?

Use of specified procedures to evaluate abilities, behaviours, and personal qualities

Referred to as the ‘measurement of individual difference'

Systematic procedures and measurement used to assess individuals functioning, aptitudes, abilities and mental states. Three requirements Reliability Validity Standardisation Features of formal assessment

Systematic procedures and measurement used to assess individuals functioning, aptitudes, abilities and mental states.

Three requirements

Reliability

Validity

Standardisation

Reliability is the stability or consistency of scores produced by an instrument Measured over time and space Concept of reliability

Reliability is the stability or consistency of scores produced by an instrument

Measured over time and space

Types of reliability Test-retest Reliability Test on two occasions Measured by a correlation Parallel Forms Different versions of a test Internal Consistency Similar scores across different parts Split-half Reliability Odd vs even numbers on test Time 1 Time 2 Form A Form B 1, 3, 5, 7 = 2, 4, 6, 8 =

Test-retest Reliability

Test on two occasions

Measured by a correlation

Parallel Forms

Different versions of a test

Internal Consistency

Similar scores across different parts

Split-half Reliability

Odd vs even numbers on test

Concept of validity Extent to which a test measures what it was intended to measure Face validity: Surface content matches Criterion/Predictive Validity: A standard e.g. your uni entry score Construct Validity: Measures the construct (e.g., depression)

Extent to which a test measures what it was intended to measure

Face validity: Surface content matches

Criterion/Predictive Validity: A standard e.g. your uni entry score

Construct Validity: Measures the construct (e.g., depression)

Norms Standards based on measurements of a large group of people Used to compare Standardisation Uniform procedures for treating each participant in a test, interview or in research Norms and standardisation

Norms

Standards based on measurements of a large group of people

Used to compare

Standardisation

Uniform procedures for treating each participant in a test, interview or in research

Extremes of intelligence?

Normal curve Standardized tests establish a normal distribution of scores on a tested population in a bell-shaped pattern called the normal curve.

Extremes of intelligence A valid intelligence test divides two groups of people into two extremes: the mentally retarded (IQ 70) and individuals with high intelligence (IQ 135). These two groups are significantly different.

Intellectual disability Onset before 18 years old IQ of below 70 to 75 Limitations in 2+ adaptive life skills Learning disorders Large discrepancy between an individual's measured IQ and achievement Extremes of intelligence

Intellectual disability

Onset before 18 years old

IQ of below 70 to 75

Limitations in 2+ adaptive life skills

Learning disorders

Large discrepancy between an individual's measured IQ and achievement

Intellectual disability

Intellectually disabled people required constant supervision a few decades ago, but with a supportive family environment and special education they are more able to care for themselves. Intellectual disability

IQ score above 130 Joseph Renzulli Three-ring conception Ability Creativity Task commitment Intellectual giftedness

IQ score above 130

Joseph Renzulli

Three-ring conception

Ability

Creativity

Task commitment

Contrary to popular belief, people with high intelligence test scores tend to be healthy, well adjusted, and unusually successful academically. High intelligence

Theories of intelligence

Psychometrics = science of mental testing Statistical relationships (factor analysis) Charles Spearman Spearman’s “g” Raymond Cattell Crystallised and Fluid Intelligence Psychometric theories of intelligence

Psychometrics = science of mental testing

Statistical relationships (factor analysis)

Charles Spearman

Spearman’s “g”

Raymond Cattell

Crystallised and Fluid Intelligence

Spearman proposed that general intelligence (g) is linked to many clusters that can be analyzed by factor analysis. e.g., people who do well on vocabulary examinations do well on paragraph comprehension examinations, a cluster that helps define verbal intelligence. Other factors include a spatial ability factor, or a reasoning ability factor. General Intelligence

General intelligence Thurstone, a critic of Spearman’s g, suggested seven clusters of PRIMARY MENTAL ABILITIES: Word Fluency Verbal Comprehension Spatial Ability Perceptual Speed Numerical Ability Inductive Reasoning Memory

Word Fluency

Verbal Comprehension

Spatial Ability

Perceptual Speed

Numerical Ability

Inductive Reasoning

Memory

Content Product Operation Guilford's structure of the intellect

Content

Product

Operation

Wechsler developed the Wechsler Adult Intelligence Scale (WAIS) and later the Wechsler Intelligence Scale for Children (WISC), an intelligence test for preschoolers. David Wechsler

WAIS measures overall intelligence and 11 related aspects to assess clinical and educational problems. David Wechsler

Analytical intelligence Basic information processing skills Creative intelligence Ability to deal with novel versus routine problems Practical intelligence Ability to adapt to different contexts, and to select and shape contexts Robert Sternberg's Triarchic Theory

Analytical intelligence

Basic information processing skills

Creative intelligence

Ability to deal with novel versus routine problems

Practical intelligence

Ability to adapt to different contexts, and to select and shape contexts

Gardner (1983, 1999) supports Thurstone’s idea that intelligence comes in multiple forms. Gardner noted that brain damage may diminish one type of ability but not others e.g., savants. Howard Gardner’s Theory of Multiple Intelligences

Gardner (1983, 1999) supports Thurstone’s idea that intelligence comes in multiple forms.

Gardner noted that brain damage may diminish one type of ability but not others e.g., savants.

8 types of intelligence - speculates about a 9th – existential intelligence = ability to think about the question of life, death and existence. Logical-mathematical, linguistic, naturalist, musical, spatial, bodily kinesthetic, interpersonal, intrapersonal (emotional) Howard Gardner’s Theory of Multiple Intelligences

8 types of intelligence - speculates about a 9th – existential intelligence = ability to think about the question of life, death and existence.

Logical-mathematical, linguistic, naturalist, musical, spatial, bodily kinesthetic, interpersonal, intrapersonal (emotional)

Howard Gardner’s Theory of Multiple Intelligences

Theories of intelligence

What does intelligence influence?

Brain function Studies of brain functions show that people who score high on intelligence tests perceive stimuli faster, retrieve information from memory quicker, and show faster brain response times.

Aptitude tests are intended to predict your ability to learn a new skill and achievement tests are intended to reflect what you have already learned. Aptitude and achievement tests

What influences intelligence?

In the past 60 years, intelligence scores have risen steadily by an average of 27 points. Flynn Effect

Schooling is an experience that pays dividends, which is reflected in intelligence scores. Increased schooling correlates with higher intelligence scores. Schooling effects

5 minute break – have a stretch

Intelligence: Issues and Controversies

Despite general agreement among psychologists about the nature of intelligence, two controversies remain: Is intelligence a single overall ability or is it several specific abilities? With modern neuroscience techniques, can we locate and measure intelligence within the brain? Controversies about intelligence

Is intelligence a single overall ability or is it several specific abilities?

With modern neuroscience techniques, can we locate and measure intelligence within the brain?

History of Group Comparisons Heredity and IQ Heritability The politics of intelligence

History of Group Comparisons

Heredity and IQ

Heritability

Environments and IQ Judith Kearins’ series of studies: No single explanation for behaviour Culture and the validity of IQ tests Graham Chaffey Invisible underachievers Claude Steele Stereotype threat (vulnerability) Harold Stevenson Hard work versus innate ability The politics of intelligence

Environments and IQ

Judith Kearins’ series of studies: No single explanation for behaviour

Culture and the validity of IQ tests

Graham Chaffey

Invisible underachievers

Claude Steele

Stereotype threat (vulnerability)

Harold Stevenson

Hard work versus innate ability

No other topic in psychology is so passionately followed as the one that asks the question, “Is intelligence due to genetics or environment?” The politics of intelligence

No other topic in psychology is so passionately followed as the one that asks the question, “Is intelligence due to genetics or environment?”

Studies of twins, family members, and adopted children together support the idea that there is a significant genetic contribution to intelligence. The politics of intelligence

Two disturbing but agreed upon facts: Racial groups differ in their average intelligence scores. High-scoring people (and groups) are more likely to attain high levels of education and income. Group differences in IQ scores

Racial groups differ in their average intelligence scores.

High-scoring people (and groups) are more likely to attain high levels of education and income.

If we look at racial differences, white Americans score higher in average intelligence than black Americans (Avery et al., 1994). European New Zealanders score higher than native New Zealanders (Braden, 1994). Group differences in IQ scores White-Americans Black-Americans Average IQ = 100 Average IQ = 85

Differences in intelligence among these groups are largely environmental, as if one environment is more fertile in developing these abilities than another. Environmental effects

Adoption studies Adopted children show a marginal correlation in verbal ability to their adopted parents.

Adoption studies Studies of twins and adopted children also show the following: Fraternal twins raised together tend to show similarity in intelligence scores. Identical twins raised apart show slightly less similarity in their intelligence scores.

Fraternal twins raised together tend to show similarity in intelligence scores.

Identical twins raised apart show slightly less similarity in their intelligence scores.

Adoption studies Early neglect from caregivers leads children to develop a lack of personal control over the environment, and it impoverishes their intelligence. Romanian orphans with minimal human interaction are delayed in their development.

Goal of psychological assessment To make as accurate assessments as possible Controversial area for psychology Three ethical concerns Fairness of test-based decisions Utility of tests for evaluating education Implications of using test scores to categorise people Assessment and society

Goal of psychological assessment

To make as accurate assessments as possible

Controversial area for psychology

Three ethical concerns

Fairness of test-based decisions

Utility of tests for evaluating education

Implications of using test scores to categorise people

Intelligence and Creativity

Creativity: Ability to generate ideas or products that are novel and useful to the circumstance Is creativity linked to intelligence? Creativity

Creativity:

Ability to generate ideas or products that are novel and useful to the circumstance

Is creativity linked to intelligence?

Intelligence and Creativity Some correlation with intelligence. Expertise: A well-developed knowledge base. Imaginative Thinking: The ability to see things in novel ways. Adventuresome Personality: Seeks new experiences rather than following the pack. Intrinsic Motivation: A motivation to be creative from within. A Creative Environment: A creative and supportive environment allows creativity to bloom.

Some correlation with intelligence.

Expertise: A well-developed knowledge base.

Imaginative Thinking: The ability to see things in novel ways.

Adventuresome Personality: Seeks new experiences rather than following the pack.

Intrinsic Motivation: A motivation to be creative from within.

A Creative Environment: A creative and supportive environment allows creativity to bloom.

Divergent Thinking defined Ability to produce unusual but appropriate responses to problems Fluid versus flexible thinking Weak to moderate correlation between IQ and Divergent Thinking Assessing creativity and the link to intelligence

Divergent Thinking defined

Ability to produce unusual but appropriate responses to problems

Fluid versus flexible thinking

Weak to moderate correlation between IQ and Divergent Thinking

Exemplary Creator Extraordinary abilities (e.g. Pablo Picasso) Risk Taking Uncharted Waters Preparation Acquisition of expertise Intrinsic Motivation Enjoyment and satisfaction Extremes of creativity

Exemplary Creator

Extraordinary abilities (e.g. Pablo Picasso)

Risk Taking

Uncharted Waters

Preparation

Acquisition of expertise

Intrinsic Motivation

Enjoyment and satisfaction

Gerrig, R. J., Zimbardo, P. G., Campbell, A. J., Cumming, S. R., & Wilkes, F. J. (2008). Psychology and life (Australian edition). Sydney: Pearson Education Australia. References

Gerrig, R. J., Zimbardo, P. G., Campbell, A. J., Cumming, S. R., & Wilkes, F. J. (2008). Psychology and life (Australian edition). Sydney: Pearson Education Australia.