Chapter 11

Intelligence

• The Mental Rotation Test Which two of the other circles contain a configuration of blocksidentical to the one in the circle at the left?

Standard Responses

1 2 3 4

Assessing Intelligence

Reliability• the extent to which a test yields

consistent results• assessed by consistency of scores on:• two halves of the test• alternate forms of the test• retesting

Validity• the extent to which a test measures or

predicts what it is supposed to

Measuring Individual Differences

The second part of a credible test is reliability. • Reliability: A test yields the same results over

time-Test-Retest or Split-Half Reliability

Reliable, but not valid

Not reliable, not valid

Reliable and valid

Content Validity• the extent to which a test samples

the behavior that is of interest • driving test that samples driving tasks

Criterion Validity: The behavior (such as college grades) that a test (such as the SAT) is designed to predict

Predictive Validity: The success with which a test predicts the behavior it is designed to predict.

Child with high IQAdult with high IQ

Assessing Intelligence

As the range of data under consideration narrows, its predictive power diminishes

Greater correlationover broad rangeof body weights

10

9

8

7

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4

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2

1

0

Little corre-lation withinrestricted

range

Football linemen’s

success

Body weight in pounds180 250 290

What is Intelligence?Intelligence• ability to learn from experience, solve problems, and use knowledge to adapt to new situations

So how do we test intelligence?

Design your own intelligence test

Develop as few as 3 to as many as 10 questions that accurately measure the intelligence of your classmates.

Then try it out!

Origins of Intelligence Testing

Intelligence Test a method of

assessing an individual’s mental aptitudes and comparing them to those of others, using numerical scores

Origins of Intelligence Testing

Stanford-Binet• the widely used

American revision of Binet’s original intelligence test-revised by

Terman at Stanford University

Mental Age• a measure of intelligence test performance

devised by Binet• chronological age that most typically

corresponds to a given level of performance• child who does as well as the average 8-

year-old is said to have a mental age of 8• 12-year-old who responded to the original

Stanford-Binet with the proficiency typical of an average 9-year-old was said to have an IQ of 75.

Origins of Intelligence Testing

Intelligence Quotient (IQ)• defined originally the ratio of

mental age (ma) to chronological age (ca) multiplied by 100 -IQ = ma/ca x 100)

• Contemporary test have created a standard sample to compare test results. The average performance for a given age is assigned a score of 100

What is Intelligence?

Factor Analysis• Determines primary components of

intelligence• used to identify different dimensions of

performance that underline one’s total score

General Intelligence (g)• factor that Spearman and others

believed underlies specific mental abilities

• measured by every task on an intelligence test

General Intelligence (g)• Spearman believed that all

multiple intelligences could essentially be evaluated by a single kind of intelligence- the “g factor”

• Most people who had good verbal skills were also typically successful at solving the novel questions on a general intelligence test.

What is Intelligence?

Social Intelligence• the know-how involved in

comprehending social situations and managing oneself successfully

Emotional Intelligence• ability to perceive, express,

understand, and regulate emotions

Creativity• the ability to produce novel and

valuable ideas-expertise-imaginative thinking skills-venturesome personality-intrinsic motivation-creative environment

Look up here.

You are about to undergo a test.

You will have a figure flashed in front of your eyes for less than a second, pay close attention to it.

Brain Function and Intelligence

People who can perceive the stimulus very quickly tend to score somewhat higher on intelligence tests Stimulus Mask

Question: Long side on left or right?

Assessing IntelligenceStandardization

defining meaningful scores by comparison with the performance of a pretested “standardization group”

Changes perspectives- percentage of people diagnoses with mental retardation increased with IQ tests were restandardized.

Aptitude Test• a test designed to predict a

person’s future performance• aptitude is the capacity to learn

Achievement Test• a test designed to assess what a

person has learned

The Wonderlic Personnel Test

Intelligence best known for it’s use on Athletes-Only non-athletic test that affects draft picks for NFL players

Try it out for yourself!

Assessing Intelligence

Wechsler Adult Intelligence Scale (WAIS)• most widely used intelligence test• subtests• verbal • performance (nonverbal)

The Normal Curve

Judging Normal• A “normal curve” is

applied to test to determine establish “norms.” When a statistically significant sample of the population has been tested, strong conclusions can be drawn.• A normal range for IQ

scores is 70-130. Scores below 70 indicate mental retardation while scores above 130 are considered gifted.

Assessing Intelligence: Sample Items from the WAIS

From Thorndike and Hagen, 1977

VERBAL

General Information Similarities Arithmetic ReasoningVocabularyComprehensionDigit Span

PERFORMANCE

Picture Completion Picture ArrangementBlock DesignObject AssemblyDigit-Symbol Substitution

Getting Smarter?

The Dynamics of Intelligence

Mental Retardation• a condition of limited mental ability• indicated by an intelligence score below

70• produces difficulty in adapting to the

demands of life• varies from mild to profound

Down Syndrome• retardation and associated physical

disorders caused by an extra chromosome in one’s genetic makeup

Are There Multiple Intelligences?

Savant Syndrome condition in which a person otherwise

limited in mental ability has an exceptional specific skill-computation -drawing

Components of Intelligence• Savant Syndrome: Individuals

with remarkable, but rare talent, even though they are mentally deficient in other areas.• Ex. Dustin Hoffman in Rain Man

The Dynamics of Intelligence

Types of Tests

There are two main types of tests:Objective Tests: Tests that have one set

answer, that can be scored easily by machine• Ex. Multiple choice

Subjective Tests: Tests in which individuals are given ambiguous figures or an open ended question which requires some interpretation and analysis.• Ex. FRQs

-Inter-rater reliability

Sample Subjective Test

The Rorschach Inkblot Test is one of the most widely known, and inaccurate subjective tests.

No one can agree on how to interpret the results!!

Genetic InfluencesHeritability• Intelligence is partially genetic, but

not entirely.• Parents IQ is the best known

indicator of how intelligent a child’s IQ will be, but this is not entirely reliable.

• Intelligent parents tend to have intelligent kids, but those kids are often times given the means to succeed.

• The heritability of intelligence is lowest among genetically similar individuals who have been raised in dissimilar environments.

Genetic Influences

The most genetically similar people have the most similar scores

Genetic Influences

So if intelligence is partially hereditary, can we take advantage of it?

EUGENICS- Movement aimed to selectively breed

intelligent people together in hopes in eventually create a smarter human race.

Gifted Programs- are they good?

Good-Encourage achievement in able

minded students

Bad- Work on intellectual growth of high

achieving students while leaving the lower achieving students behind

Downside of IQ Testing• Despite its utility, IQ testing had a

big downside. Tests ended up reinforcing prevailing prejudices about race and gender.

• Ignored was the fact that environmental disadvantages limit the full development of people’s intellectual abilities.

• Same problem of NCLB!!!

Downside of IQ Testing

Poor nutrition can lead to lower IQ scores

Differences in cultural values can lead to differences in IQ scores

Environmental Influences

The Schooling Effect

Group Differences

Group differences and environmental impact

Variation within group

Variation within group

Difference within group

Poor soil Fertile soil

Seeds

Group Differences

Stereotype Threat• A self-confirming concern that one will be evaluated based on a negative stereotype

Theories of Intelligence

• Howard Gardner believed that IQ scores measured only a limited range of human mental abilities. He argued we have seven separate mental abilities he calls the multiple intelligences.

• Linguistic intelligence ("word smart"):• Logical-mathematical intelligence

("number/reasoning smart")• Spatial intelligence ("picture smart")• Bodily-Kinesthetic intelligence ("body

smart")• Musical intelligence ("music smart")• Interpersonal intelligence ("people

smart")• Intrapersonal intelligence ("self smart")

Theories of Intelligence