E-411 PRMA
Week 6 - Intelligence and Factor Analysis
This week
Intelligence
Factor Analysis
Intelligence
What is intelligence?
What makes someone intelligent?
Intelligence is ...
There is no consensus on what intelligence is
There is no single instrument to measure intelligence
To Sternberg's public, intelligence means
"Reasons logically and well"
"Reads widely"
"Displays common sense"
"Keeps an open mind"
"Reads with high comprehensions"
Intelligence could involve ...
Problem-solving ability
Verbal ability
Social competence
Interactionist views of intelligence
Galton - possessing great sensory (hearing, visual) abilities
Binet - intelligence involves reasoning, judgment, memory, and abstraction and these cannot be seperated
Wechsler - intelligence is an aggregate capacity made of measurable, qualitatively different abilities that interact in a complex, non-additive fashion
Wechsler - measurement of intelligence affected by nonintellective factors
Piaget - evolving biological adaption to the world
Factor analysis and intelligence
Spearman (1927), existence of a general ability factor, g and specific factors, s
Intelligence tests with high correlations possess high g
Group factors common to a group of activities but not g
Thurstone purposed a 7 factor structure of intelligence but could not escape g
Gardner adds interpersonal (working with others) and intrapersonal (working with yourself)
Motivation for the CHC model
Cattell proposed a theory of intelligence that consists of crystallized and fluid intelligence
crystallized intelligence, Gc, ability to use skills, experience, & knowledge (e.g. retrieving and applying information)
fluid intelligence, Gf, capacity for solving novel problems
Horn added additional factors Gs
Carroll proposed a 3 layered hierarchical view with g on the top, then factors similar to Cattell's and Horn's, and specific factors depending on the second-level factors
Carroll's model
CHC model
McGrew and colleagues tried to reconcile these approaches
Proposed a modified Carroll model without a g
Omission of g based on the lack of utility for their needs
McGrew calls for adoption of the CHC model and made data available here
CHC model
There are 10 broad-stratum abilities
fluid, crystallized, quantitative knowledge, reading/writing ability, short-term memory, visual processing, auditory processing, long-term storage/retrieval, processing speed (perform automatic cognitive tasks, couple minutes), and decision time/speed (reaction time, couple seconds)
There are 70 narrow-stratum abilities
Information-processing framework
Rather than using factor analysis to derive "what" intelligence is, examine how information is processed
simultaneous processing, integration at once
successive processing, sequential integration
Extant tests do not take into account problem solving strategy
Sternberg proposed successful intelligence, how well we adapt, share, shape, select environments that confirm to personal and societal success
How to measure intelligence?
- Myriad of tasks developed depending on age of testtaker
- Infants focused on sensorimotor skills; shift towards verbal and performance abilities as children age
- Mental age has fallen out of favor
- For children, tests often used for school placement
- Adults, test more diverse and typically used clinically
Problems in intelligence
Nature vs. nurture
- Preformationism & predeterminism - slave to your genes
- Twin studies
- Interactionist view - unlimited potential
Stability
- Young adult intelligence most important predictor of intelligence of older adults
- Aging, physical/mental health, medications - confounders
- "Early ripe, early rot"
More problems
Flynn effect - rise in intelligence test scores expected to occur on a normed intelligence test from the date the test was first normed.
Personality \(\equiv\) Intelligence
Gender differences?
Family effects starting in the womb?
Cultural considerations? Culture-loading and creation of culture-fair tests
Stanford-Binet IQ test
- Conceived by Binet to screen for children with developmental disabilities
- Originally intelligence calculated as the ratio of mental age to true age
- Deviation score, mean of 100 and standard deviation of 15
- Measures fluid reasoning (fluid), knowledge (crystallized), quantitative knowledge, visual-spatial, and working memory (see Table 10 - 2)
- Adaptive
Fifth edition
Full scale IQ from ten subtests
Subtest scores can be combined to get other composite scores (e.g. verbal score)
Standardized for the USA population aged 2 to 85
Manual reports high internal consistency, test-restest, and inter-rater reliability (though items with low reliability were pruned)
Criterion-Related VE from concurrent and predictive data
Use in a clinical population and factor structure unclear
Weschler intelligence tests
Age-appropriate tests for very young children, children, adults
All originally used a verbal, performance, and FSIQ, now only young children uses V and P scales
Many subtests and items specific just to Weschler's tests (Table 10 - 3)
Consists of core subtest and supplementals used to extract clinical information
Short forms exist, but discouraged
Good psychometric properties
Comparison and other tests
Both purport to measure intelligence
Highly correlated, differ by amount of g
Both work within the CHC model
Both represent gold standard
Different factor structures and definitions of intelligence
Kaufman tests focus on processing not structure
Group tests
USA army developed tests for recruits in WWI
Alpha, those who could read, Beta, those who couldn't
Assigned duty and service based on performance
Tests used in post-war because they were much cheaper
Later, Army General Cliassification Test and Armed Service Vocational Aptitute Battery
Also used in the schools in the USA for placement (not as much now)