1. Intelligence & General Ability Testing
PSY 504: Psychological Measurement

2. Models of Intelligence
Cattel-Horn-Carroll Model
Sternberg’s Triarchic Theory
Ceci’s Bioecological Model
Gardner’s Multiple Intelligences

3. Cattell-Horn-Carroll Model
One of the more influential contemporary theories
g is composed of two second-order factors
Fluid abilities (Gf)
Biologically determined and affect all fields of relational perception
Relatively culture free and often reflected in memory span and spatial thinking tests
Crystallized abilities (Gc)
Include acquired skills and knowledge that are influenced more by cultural, social, and educational experiences
Representative tests include verbal comprehension and social relationships

4. Sternberg’s Triarchic Theory
Componential Intelligence – ability to process information at the metacomponent, performance, and knowledge-acquisition levels; ability to think abstractly and process information effectively
Analytical/Conventional Intelligence (“Book Smarts”)
Experiential Intelligence – relationship between experience and intelligence; ability to formulate new ideas and new solutions to problems; ability to combine new information
Creative Intelligence
Contextual Intelligence – contextually bound; ability to adapt to changing environmental conditions and to shape the environment; ability to understand people
Practical Intelligence (“Street Smarts”)

6. Ceci’s Bioecological Model
Biological factors have a major influence on intelligence, but there is no single, underlying factor (g), nor is intelligence highly heritable
There are no intelligent people, only people who are intelligent in certain domains
Intellectual abilities are highly influenced by context in which they are performed

7. Gardner’s Multiple Intelligences
Any set of adult competencies that are valued in a culture merits consideration as a potential intelligence
9 relatively independent “frames of mind”
Verbal--Linguistic
Logical--Mathematical
Musical--Rhythmic
Visual--Spatial
Bodily--Kinesthetic
Interpersonal
Intrapersonal
Naturalist
Existential
Measures need to value intellectual capacities in a wide range of domains, and the methods should be appropriate for the domain

9. Individual Intelligence Testing
Wechsler Scales
Stanford-Binet Intelligence Scale

10. Wechsler Scales
Wechsler Preschool and Primary Scale of Intelligence – IV (WPPSI-IV)
Wechsler Intelligence Scale for Children – V (WISC-V)
Wechsler Adult Intelligence Scale – IV (WAIS-IV)
Wechsler Memory Scale – IV (WMS-IV)

11. WISC-V
Full Scale IQ – based on the 5 Primary Index Scales (16 core subtests)

12. WAIS-IV
Full Scale IQ – based on the 4 Index Scores (10 core subtests; 5 supplemental)

13. Wechsler Scales Reliability Validity Conclusions
Full Scale IQs on the entire battery have reliabilities that range from
The Index scores have reliabilities that range from
Validity Conclusions
Much strength is attributed to the Wechsler Scales based upon the size and representativeness of the standardization samples (especially adult and preschool populations); and technical qualities of their test construction procedures
Very popular intelligence scales = much research

14. Wechsler Scales
Many ancillary materials: computer-assisted interpretive programs, manuals for training examiners, and interpretive guides
Some criticism due to demands for links between assessment instruments and intervention strategies (hence, movement towards Index scores)
i.e., lack of theoretical grounding = influences interpretation
Some do not think a theoretical grounding is necessary

15. Stanford-Binet Intelligence Test – 5
For use with individuals 2 years – 85 years
Verbal IQ, Nonverbal IQ, Full Scale IQ
Five factors for both verbal and nonverbal areas:
Fluid Reasoning
Knowledge
Quantitative Reasoning
Visual-Spatial Processing
Working Memory
Basal and ceiling levels

16. Stanford-Binet Intelligence Test – 5
Reliability
Composite scores on the entire battery have reliabilities at all age levels, ranging from
Most subtests have reliabilities from the high 0.80s to low 0.90s
Validity Conclusions
Correlates well with measures of achievement
Can distinguish between mentally retarded, gifted, and neurologically impaired persons
Instrument of choice for evaluating gifted children because of the high ceiling provided by the age range of the test
Lacks floor items that are low enough to diagnose mental retardation among the youngest test takers

17. Is Intelligence Stable?
Infants and young children have the least stable intelligence test scores
Early research indicated intelligence gradually declines after age 20 – not supported by later research
More recent research indicates intelligence gradually increases from childhood to middle age and then levels off
Declines tend to occur in areas of fluid intelligence after the age of 65
Fluid – tests that require speed of processing and mental manipulation
Crystallized – tests that measure experience and knowledge

18. What Do Intelligence Scores Predict?
Intelligence tests appear to be related to academic performance with correlations near 0.50 (remember, this means on 25% of the variance is explained)
The relationships among IQ scores, occupational success, and income are not simple

19. Is Intelligence Hereditary?
One of the most controversial issues in intelligence testing
Determining estimates of the genetic contribution to intelligence is difficult
In general, the heritability indexes for intelligence tend to be approximately 0.50
Both genetic and environmental factors have significant effects on intellectual development, with IQ scores seemingly to be related to the interaction between the two

20. What Environmental Factors Influence Intelligence?
Culture and language
School attendance
Children who attend school regularly have higher tests scores than children who attend intermittently
Important to note that not all schooling is alike and that the quality of the school experience also influences IQ scores
Family environment
Severely neglectful or abusive environments can negatively affect children’s cognitive development
Environmental toxins
Exposure to lead and prenatal exposure to large amounts of alcohol have been well documented to have deleterious effects on children

21. Are There Group Differences in Intelligence?
Important to note that within-group variance is often greater and between-group variance
Gender
There do not appear to be general intellectual differences between men and women
Men may be better at visual-spatial tasks
Women may be better at verbal tasks
Ethnicity
African-Americans, Hispanics, and Native Americans tend to score lower on intelligence tests than European-Americans or Asian-Americans
Differences often due to socioeconomic influences, linguistic factors, culture factors, and possibly “test bias”

22. The Flynn Effect
James Flynn was the first to identify steadily increasing intelligence test scores across generations
From the 1940s to early 21st century, the average IQ score has increased more than one full standard deviation
Gains in IQ not reflected in gains in achievement
Possible explanations: better nutrition, decrease in the intensity of infectious diseases, more test sophistication, changes in education and opportunities, changes in parenting practices, more complex and stimulating environment
*There may now be a reversed Flynn effect – i.e., decline in IQ scores, which may have started in the 1990s