Chapter 9 - Intelligence

Definition

• Classic = verbal reasoning& visual-spatial problem-solving

• Neglects other aspects

Theories of Intelligence

A. Psychometric Theory

• Traits on which individuals differ

• Findings:

- General mental ability (Spearman’s g)

- S (special abilities)

- Verbal vs. problem-solving

- Fluid vs. crystallized

IQ & Aging

• Crystallized increases through life

• Fluid increases to young adulthood, then declines

• Slower processing speed

• IQ tests based on psychometric theory

• But only measure part of intelligence

Sternberg’s Triarchic Theory

• Information-processing

• How person processes information

3 Aspects of intelligent behavior:• Context

- “intelligent” depends on context• Experience

- doing well on familiar tasks is NOT intelligence

- task must pose a challenge

- BUT automatizing common tasks = intelligence

• Components/skills

- must examine person’s cognitive processes in addition to answers

Incorporating into assessment• Test behavior

- how person approaches tasks

(components/skills)• Background

- parents’ occupations & home environment

(experience)• Other observations (context)

Measuring Intelligence• Test Construction

- Select items

- Norms

Administer to standardization sample

Scoring standards are based on group’sperformance

Group should be representative

- Standardized Testing

Give test in same way to everyone

- Reliability

Assess the test’s consistency

(over time, over examiners, etc.)

IQ is stable

Reliability & Error

X = T + E

• X = person’s score

• T = person’s actual ability

• E = error in measuring person’s ability

Sources of Error

1. Person taking the test

2. Situation

3. Examiner

4. Test content

5. Time

- Validity

Does test measure what it is supposedto measure?

Compare test performance with related

behavior

Infant & Toddler Tests

• Measure development

- not IQ (& may not be correlated)

- how close development is to average for age (DQ)

- to identify children at risk

Gesell Developmental Scales

• 4 scales (adaptive, motor, language, personal-social)

• Normed on small group of middle-class kids

Bayley Scales (2-30 months)

- ability to manipulate toys

• Mental Scale - learning

• Motor Scale - controlling body

• Behavior Record - emotional adjustment

• Most commonly used

• Normed on 1,700 normal kids

race/sex/geographic area/urban-rural/parent education

Child & Adult Tests

History

Binet-Simon Scale - First intelligence test (1905)• To identify “dull” kids for remedial work• Test was reliable• Test distinguished dull, average, bright by teacher

ratings• Reliable & valid

Binet: mental age

• Age at which child performs

Stanford-Binet (for ages 3-13)

• 1916 – Terman

• Normed on 1000 American kids

Terman: intelligence quotient (IQ)

= MA x 100

CA

100 is average (MA=CA)

- To compare kids at different ages

- Problem: Still gives age at which child performs, not comparison to own agemates

Deviation IQ

• Compare kids to same-age peers

4 Main Tests

Stanford-Binet (2-90+)• 2 hours• Norms are representative (4,800 people)

(SES, race, age, sex)• 15 subtests• IQ + other scores

Pros:

• Best test for very high/low IQs****

• Wide age span

• 2 equivalent forms

• Excellent norms

Cons:

• Lengthy

• Difficult to administer

• Lower examiner reliability

3 Wechsler Tests .5-1.5 hours

• WPPSI-III (2.6-7.3) WISC-IV (6-16.11)

WAIS-III (16-89)

• Also WASI (brief, ages 2-89)

• 11-13 subtests

• IQ + other scores

Subtests

Verbal

• Information

• Digit Span

• Vocabulary

• Arithmetic

• Comprehension

• Similarities

Visual-Spatial

• Picture Completion

• Picture Arrangement

• Block Design

• Object Assembly

• Digit Symbol

Pros:

• Shorter

• Easier to administer

• Most commonly used

• Census-based norms

• Can compare performance across ages/tests

• For ages 6, 7 & 16, can pick best test

Con:

• Not as useful for IQ extremes

- important for MR

Wechsler IQ Classifications

130+ Very Superior

129-129 Superior

110-119 High Average

90-109 Average

80-89 Low Average

70-79 Borderline

<69 Mentally Retarded

K-ABC (2.5-12.5) 45-75 minutes

• No IQ score

• Composite

• Sequential/Simultaneous Processing

- Sequential = in a series

- Simultaneous = together

Pros:

• Differences in Seq/Sim can suggest interventions

• Flexible administration (hints, prompts)

• Short/quick

Cons:

• Unclear distinction between Sequential & Simultaneous

• Shorter age range

• Norms under-represent disadvantaged blacks & Hispanics**

McCarthy Scales (2.5-8.5)

• 45-60 minutes

• No IQ

• General Cognitive Index + 6 subscales

Pros:

• Gives profile of abilities

- for kids with learning problems

• Includes motor coordination

• Census-based norms

• Very short

Cons:

• Few abstract or social judgment problems

• Restricted age range*

Use of IQ tests

Historically

• 1905 - to identify kids needing remediation

• 1940s & 50s - widely given to categorize

• 1960s - aware of abuses, testing declined

Current uses

• To diagnose problems

• To rule out IQ problems

• To identify ways to help

NOT simply to place children in classrooms

To diagnose a learning disability

• Normal intelligence (IQ)

• Performing below level in 1+ subject(on achievement test)

Factors that Influence IQ Scores

Heredity – Family, Twin, & Adoption StudiesIQ correlations are higher:• For more closely related people• For MZ than for DZ twins• For MZ than for non-twin siblings• For biological relatives

- grows with age (3 vs. 7)

Strong influence of heredity on IQ

Environment/Socioeconomic Status (SES)

• Twin & Family studies

- imperfect correlation for MZ twins

- correlations higher if raised together

• Adoption Studies

- some correlation with adoptive parents & siblings

• Impoverished Environments- lower than average IQs for kids in poor communities

• Enriched Environments- when community is enriched, average IQ rises- impoverished kids placed in advantaged adoptive families show IQ increases

• IQ does correlate with SES

• Significant influence of environment/SES

Race - General findings

• Asian > Caucasian > Hispanic > African-American/Native American

Much overlap among the groups

• More variability within than between groups

• Group differences don’t explain why

• Group differences don’t address any individual’s performance

• Differences often accounted for by SES

4 Theories1. Genetic - Jensen/Rushton

• Racial differences are genetic because they are stable

• Because IQ is equally due to genetics within any race, differences between races must also be due to genetics

Criticism:

• Individual differences may be genetic and group differences may be environmental

Rushton: More “white” genes = smarter person

Findings:• IQs of mixed-race kids are not lower than IQs of

Caucasians• IQs of blacks don’t differ by number of white

ancestors

-> NO support for genetic theory

2. Test Bias

• Tests measure cognitive skills & knowledge of middle-class Caucasians

• Testing culture-based experience

• Tests are in standard English

Revisions

• “Culture-fair” tests

• Revision of standard tests

Findings

• Caucasians still perform better

Conclusion

• Test bias may not be the reason

• Or tests are still culture-laden

3. Motivation

• Lower class and ethnic minority kids may be less motivated on these tests

• Discrimination

-> lower self-esteem & motivation

Findings:

• Friendly examiners & flexible administration raise IQ by 7-10 points

• K-ABC halves race difference

• But: Caucasian kids also score higher in these situations

Conclusion

• Test procedures & motivation may bias results

• But don’t fully explain race differences

4. Environment/SES

• Low SES environments are less conducive to intellectual development

• Parents may have fewer resources

Evidence

• African-American kids who move to better environments show IQ jumps

• Lower-class African-American kids adopted into middle-class homes have average+ IQs

• SES statistically accounts for most racial differences****

• SES is strongest explanation

• Test bias & motivation may play more subtle roles

Mental Retardation

Definition

• Subaverage intellectual functioning

- IQ < 70

• AND poor adaptive behavior skills

- pattern of low functioning

MR Levels

1.Mild (55-69) - “Educable” - majority

• Often self-sufficient

• May reach 3rd - 6th grade level

Moderate (35-55) - “Trainable”

• Developmental delays

• Simple communication

• Sheltered workshops

Severe (20-35)

• Large developmental delays

• Understand some speech

• Routines & supervision

• Some daily living skills

Profound (< 20/25)

• Nursing care

• May not be able to walk/talk

• Poor/no daily living skills

Life Outcomes

All retarded people (mild/moderate)• Worse than non-retarded peers• But better than stereotypes suggest

- majority (80%) of males work

skilled labor & retail

- most are self-supporting

- most married

- life satisfaction

• Conclusion

- Sternberg’s contextual intelligence

(not measured with IQ)

• Severe & Profound

- institutionalization

BUT, a very small percentage of MR population

Mentally Gifted

Terman’s “Termites” (1921)

- 1500 kids with IQ > 140

As kids• Weighed more at birth• Walked & talked sooner• Puberty earlier/health better• Mature & well adjusted• Classroom leaders

As adults

• Fewer psychological & health problems

• Higher marital/sex satisfaction

• Many college graduates

• Many notable careers

Why better in all domains?

• IQ

• Home

- parent education

- fewer divorced parents

Creativity

Definition

• No standard

• Imagination, originality

• Different from intelligence

• Reach goal in novel way

(useful & unusual)

Ways to measure:• Divergent thought - originality• Ideational fluency - many ideas• Consensual assessment

- others agree that something is creative• Remote associations

- see relationships among ideas that are remote from one another

For each set of words, think of 4th word related to all 3

• Rough Cold Beer

• Food Catcher Hot

• Hearted Feet Bitter

• Dark Shot Sun

• Canadian Golf Sandwich

• Tug Gravy Show

• Attorney Self Spending

• Magic Pitch Power

• Arm Coal Peach

• Type Ghost Story

To increase creativity:3 methods

Brainstorming

• People alone are often more creative

Synectics

• Use of analogies in creative thinking

• Look to other areas for a solution

• Used in industry but no research

Incubation

• More likely to solve difficult problem if delay between periods of work

• Plausible but seldom demonstrated

Why not more effective?

Social Factors

• Evaluation decreases creativity

Other conditions• When someone is watching you work• When you are offered a reward• When you must compete for prizes• When someone restricts your choices about how

you can express creativity

Creativity seems to be more personal/private