How is intelligence measured?
A. Binet’s test of intelligence
The concept of mental age
The intelligence quotient
The Stanford-Binet test
B. The Wechsler scales
C. Infant intelligence
The Bayley scales of infant development
Habituation and preference measures
II. What is intelligence?
A. The Psychometric view
Nature/nurture and the stability of intelligence
Is intelligence a single attribute?
Factor analysis
Spearman’s “g” and “s”
Thurstone’s primary mental abilities
Guildford’s Structure of Intellect
Cattell’s Fluid versus Crystallized intelligence
B. The information processing view
Sternberg’s triarchic theory of intelligence
Gardner’s theory of multiple intelligences
III. What do intelligence tests predict?
A. Scholastic achievement
B. Occupational status
C. Health, adjustment, and life satisfaction
IV. Common uses (and abuses) of IQ tests
A. A historical look at IQ testing
B. Uses of IQ tests
Terman’s mass testing of children
Yerkes’ army mental testing
Measures of Intelligence
The Stanford-Binet test
Alfred Binet
The Stanford-Binet test
• Mental age and chronological age
• The Intelligence Quotient (IQ)
Measures of Intelligence
The Wechsler Scales
David Wechsler
The WISC-IV (Wechsler Intelligence Scale for
Children) – 6 to 16 yrs
The WPPSI-III (Wechsler Preschool and Primary
Scale of Intelligence-Revised) – 2 to 7 yrs
Measures of Intelligence
Infant Intelligence
Nancy Bayley
The Bayley Scales of Infant Development (BSID-III)
• Cognitive, Language, Motor
• Socio-Emotional, Adaptive Behavior
• The Developmental Quotient (DQ)
Habituation and Preferential looking measures
• Speed of habituation
• Preference for novelty
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,
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
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
Questions related to spatial abilities
Structure of Intellect Model
Guildford’s (1967)
J. P. Guilford
Content: What a person thinks about
Operations: The kinds of thinking required
Products: The kinds of answers required
Fluid versus Crystallized Intelligence
(Cattell, 1971, 1984)
Raymond Cattell
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
• Ex., General information, word comprehension
Developmental flavor
Triarchic Theory of Intelligence
Sternberg (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 Intelligences
Gardner (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
• 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
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