testing and Individual Differences ❮ 227Factor analysis—a statistical procedure that identifies common factors among groups
of items by determining which variables have a high degree of correlation.
Charles Spearman used factor analysis to identify g (general factor underlying all
intelligence) and s (less important specialized abilities).
Thurstone identified seven distinct intelligence factors he called primary mental
abilities.
John Horn and Raymond Cattell identified two intelligence factors:
- Fluid intelligence—those cognitive abilities requiring speed or rapid learning that
tend to diminish with adult aging. - Crystallized intelligence—learned knowledge and skills, such as vocabulary, which
tend to increase with age.
Multiple intelligences—Howard Gardner’s theory that people process information
differently and intelligence is composed of many different factors, including at least
eight intelligences: logical-mathematical, verbal-linguistic, spatial, bodily-kinesthetic,
musical, interpersonal, intrapersonal, and naturalistic.
Emotional intelligence—Peter Salovey and John Mayer’s construct defined as the
ability to perceive, express, understand, and regulate emotions; similar to Gardner’s
interpersonal and intrapersonal intelligences.
Triarchic theory of intelligence—Robert Sternberg’s idea of three separate and test-
able intelligences: analytical (facts), practical (“street smarts”), and creative (seeing
multiple solutions).
Heredity/environment and intelligence:
Both nature and nurture contribute to intelligence.
In twin studies, correlation of IQs of identical twins was much higher than that of
fraternal twins or other siblings (favoring nature).
Flynn effect—steady increase in performance on IQ tests over the last 80 years,
possibly resulting from better nutrition, educational opportunities, and health care
(favoring nurture)
Human diversity:
Within-group differences—range of scores for variables being measured for a group
of individuals.
Between-group differences—usually the difference between means of two groups
of individuals for a common variable.
Stereotype threat—Claude Steele’s concept that anxiety influences achievement
of members of a group concerned that their performance on a test will confirm a
negative stereotype. This may account for lower scores of blacks on intelligence tests
or girls on math tests.