Session 7
Intelligence and General Ability Testing
Schedule
 Instruments we use
 Intelligence instruments
 Achievement and Aptitude
 Exam results
Widely Used Measures
 Community – MMPI, Strong-Campbell,
Myers-Briggs, WAIS-R, WISC-IV
 School – WISC-IV, PSAT, SAT, ACT, CAT,
DAT, Strong-Campbell
Overview
 No agreement in profession on either
definition or meaning of intelligence
 Sometimes called “general ability” because of
negative associations with term “intelligence”
 Debate about meaning of intelligence and
intelligence test scores is emotionally
charged
Models of Intelligence
 Psychometric Approaches
 Developmental Progressions
 Information Processing
 Multiple Intelligences
Psychometric Approach
 Major influence since turn of century
 Based on mental factors or general mental
skills that influence mental performance in a
variety of situations
 Number of factors range from Spearman’s
two factors to Guilford’s 180 factors.
Spearman (1927)
 First to discuss factors
 Two factors
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g or general ability factor that influences
performance on all intellectual tasks
specific factors that influence performance in
specific areas but highly correlated with g
 Intelligence viewed as a homogeneous
construct; either you were smart or not
Thurstone (1938)
 Proposed model of seven primary mental
abilities
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Verbal comprehension
Word fluency
Number facility
Perceptual speed
Memory
Space
Reasoning
Vernon (1950)
 Hierarchical approach
 g is first order factor
 v:ed (verbal/educational aptitudes) and k:m
(spatial/mechanical/practical aptitudes)
Cattell (1971)
 First order factor like g
 Two second order factors
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Fluid abilities (Gf) are biologically determined,
relatively culturally free and reflected in tests
of memory span and spatial abilities
Crystallized abilities (Gc) include acquired
skills and knowledge, are influenced by
cultural, social and educational experiences
and reflected in tests of verbal comprehension
and social relationships
Guilford (1988)
 Structure of intelligence theory
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First dimension is mental operations and contains six forms
Mental operations involve five content areas which is the
second dimension
Finally, there are six possible products, the third dimension,
that interact with the combinations of operations and content
areas
Developmental progressions
 Not concerned with psychometric differences
in intellectual abilities
 Interested in how intelligence develops
Piaget
 Stages of development
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Sensiomotor
Preoperational
Concrete operations
Formal operations
 Two intellectual functions
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Assimilation
Accommodation
Other developmentalists
 Vygosky – curriculum
 Neisser – biological development
 Ceci – bioecological (no g but differences in
domain-general abilities depending on
context)
Information processing
 Interested in how not what is processed
 Luria’s two methods of processing
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Simultaneous (mental ability to integrate input
all at once)
Sequential (stimuli arranged in serial order to
solve problem)
Kaufman Assessment Battery for Children (KABC)
 Sternberg’s triarachic theory
Individual Intelligence Testing
Wechsler Scales
 Wechsler Preschool and Primary Scale of
Intelligence (WPPSI-III) for kids from 2 years
6 months to 7 years 3 months
 Wechsler Intelligence Scale for ChildrenFourth Edition (WISC-IV) for kids from 6 to 16
 Wechsler Adult Intelligence Scale-Third
Edition (WAIS-III) for individuals 16 through
89
 All 3 have mean of 100 and SD of 15
WISC-IV
 Full Scale IQ plus Performance and Verbal
IQ’s
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Verbal subtests are Information, Similarities,
Arithmetic, Vocabulary, and Comprehension
Performance subtests are Picture Completion,
Coding, Picture Arrangement, Block Design,
and Object Assembly
All subtests have mean of 10 and SD of 3
 Sample report
 Technical reports
Stanford-Binet Intelligence Scale
Binet (cont’d)
 Can use with folks from 2 years through
adulthood
 Includes comprehensive coverage of five
factors--Fluid Reasoning, Knowledge,
Quantitative Reasoning, Visual-Spatial
Processing, and Working Memory (remember
Cattell?)
 Has mean of 100 and SD of 16
Kaufman Instruments
 Kaufman Assessment Battery for Children-II
 Can interpret in two ways:
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Crystallized Ability (Cattell-Horn-Carroll model)
for children from a mainstream cultural and
language background
Luria model which excludes verbal ability
 Designed for folks from 11 to 85+ years
Kaufman (cont’d)
Kaufman (cont’d)
 Difficult to interpret
 Mean of 100 and SD of 10
 Not widely used
Group Intelligence Testing
Group Test Usage
 School boards who want to evaluate school’s
performance examine differences between
ability (group IQ tests) and performance
(group achievement tests)
 Screening for further referral
Tests
 Cognitive Abilities Test, Form 6 (CogAT,
2001)
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K to 12
Separate scores for verbal, quantitative and
nonverbal reasoning plus composite
 Otis-Lennon School Ability Test, Eighth
Edition
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K to 12
Provides total, verbal and nonverbal scores
Difficulties
 Can’t observe behaviors that may indicate
level of motivation
 Require more reading
 Reliability and validity data not as strong as
for individually administered tests
Issues in Intelligence Testing
Stability of scores
 Cross-sectional (people at different age levels
tested and scored compared) studies said not
stable
 Longitudinal studies (same people tested
throughout lives) said is stable
 Combination of cross-sectional and
longitudinal suggest intelligence is fairly
stable
Prediction
 Academic performance but only 25% of
variance is explained by the relationship
 Occupational success and income some
relationship with about 1/4 related to social
status variance and 1/6 to income variance
 Highly related to job performance
 Mental processing speed important
component
Heredity and Environment
 Appears to be a hereditary influence but is
also influenced by environment
 Environmental factors such as culture,
schooling, nutrition, and exposure to certain
toxins impact intelligence
Group Differences
 Gender
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Females tend to score higher on some verbal
tasks while men are better at visual-spatial
tasks.
 Ethnicity
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African-Americans, Hispanics, and Native
Americans tend (as a group) to score lower
than do European-Americans and AsianAmericans
Flynn Effect
 Rise in intelligence test scores
 In past 50 years has risen by 1 SD
 Reasons for this rise are unclear