IntelligenceI. How is intelligence measured?

A. Binet’s test of intelligence1. The concept of mental age2. The intelligence quotient3. The Stanford-Binet test

B. The Wechsler scalesC. Infant intelligence

1. The Bayley scales of infant development2. Habituation and preference measures

II. What is intelligence?A. The Psychometric view

1. Nature/nurture and the stability of intelligence2. Is intelligence a single attribute?

a. Factor analysisb. Spearman’s “g” and “s”c. Thurstone’s primary mental abilitiesd. Guildford’s Structure of Intellecte. Cattell’s Fluid versus Crystallized intelligence

B. The information processing view1. Sternberg’s triarchic theory of intelligence2. Gardner’s theory of multiple intelligences

III. What do intelligence tests predict?A. Scholastic achievementB. Occupational statusC. Health, adjustment, and life satisfaction

IV. Common uses (and abuses) of IQ testsA. A historical look at IQ testingB. Uses of IQ tests

1. Terman’s mass testing of children2. Yerkes’ army mental testing

Measures of IntelligenceThe Stanford-Binet test

The Stanford-Binet test• Mental age and chronological age• The Intelligence Quotient (IQ)

Alfred Binet

Measures of IntelligenceThe Wechsler Scales

The WISC-IV (Wechsler Intelligence Scale for Children) – 6 to 16 yrs

David Wechsler

The WPPSI-III (Wechsler Preschool and Primary Scale of Intelligence-Revised) – 2 to 7 yrs

Measures of IntelligenceInfant Intelligence

The Bayley Scales of Infant Development (BSID-III)

Nancy Bayley

Habituation and Preferential looking measures• Speed of habituation• Preference for novelty

• Cognitive, Language, Motor• Socio-Emotional, Adaptive Behavior• The Developmental Quotient (DQ)

The Psychometric View of Intelligence

Intelligence can be thought of as a trait, or set of traits, that characterize some people to a greater extent than other people

Four different psychometric view

1. The ability to carry out abstract thinking (Terman, 1921)

2. The capacity of an individual to act purposefully and think rationally, and to deal effectively with the environment (Wechsler, 1944)

3. Innate, general cognitive ability (Burt, 1955)

4. All of the knowledge a person has acquired (Robinson & Robinson, 1965)

Factor Analysis

Test Items:1 2 3 4 5 6 7 8 9 10

Highly correlated test items:

• 1, 3, 4, 8

• 2, 5, 9, 10

• 6, 7

Factor Structure:

• Questions related to verbal ability

• Questions related to mathematical reasoning

• Questions related to spatial abilities

Structure of Intellect ModelGuildford’s (1967)

Content: What a person thinks about

Operations: The kinds of thinking required

Products: The kinds of answers required

J. P. Guilford

Fluid versus Crystallized Intelligence(Cattell, 1971, 1984)

Fluid intelligence:• The ability to solve abstract relational

problems that have not been explicitly taught and are free of cultural influences

• Ex., Verbal analogies, memory for lists, etc.

Crystallized intelligence:• The ability to solve problems that depend on

knowledge acquired in school or through other experiences

• Ex., General information, word comprehension

Developmental flavor

Raymond Cattell

Triarchic Theory of IntelligenceSternberg (2001, 2005, 2008)

Robert Sternberg

•Analytic intelligence• Information processing components that underlie all

intelligent acts• Strategies, self-regulation, metacognitive knowledge

•Creative intelligence• The ability to generate solutions to new problems• The automatization of tasks to free working memory

•Practical intelligence• Adapting to, shaping, or selecting the environment• Fit one’s desires to the demands of the environment

Theory of Multiple IntelligencesGardner (1983, 1993)

Howard Gardner

•No general intelligence• 8 (or 9 according to some) intelligences• Each has a unique biological basis, course of

development, and end-state•Problems with theory• Neurological evidence• Several dimensions have features in common

What Do Intelligence Tests Predict?

IQ and scholastic achievement• IQ predicts academic achievement• Caveats

IQ and occupational success• IQ and job prestige• IQ and job performance

IQ and health, adjustment, and life satisfaction• Terman’s longitudinal study with school

children• Family environment hypothesis

Binet’s Principles for the Use of the Intelligence Measure

1. The scores are a practical device; they do not support any theory of intellect. They do not define anything innate or permanent. We do not designate what they measure as “intelligence.”

2. The scale is a rough, empirical guide for identifying mild-retarded and learning disabled children who need special help. It is not a device for ranking normal children.

3. Whatever the cause of difficulty in children identified for help, emphasis shall be placed on improvement through special training. Low scores shall not be used to mark children as innately incapable

Gould, 1981, p. 155