1 2 Intelligence and General Ability Testing Chapter 7 Models of Intelligence Psychometric approach Cattel-Horn-Carroll model Developmental progressions Information processing 3 Other theories Psychometric Approach Based on premise that intelligence can be described in terms of mental factors (Bjorkland, 2005) Spearman s (1927) 2-factor model g (general ability factor) Specific factors 4 Guilford s (1988) structure-of-intelligence theory Mental operations Content areas Products Psychometric Approach (cont.) Thurstone s (1938) 7 primary mental abilities Verbal comprehension Word fluency Number facility Perceptual speed Memory Space Reasoning Vernon s (1950) hierarchical theory g v:ed & k:m 1
v:ed & k:m 5 6 Cattel-Horn-Carrol Model One of the more influential contemporary theories g is composed of two second-order factors Fluid abilities (Gf) Crystallized abilities (Gc) Developmental Progressions Intelligence can be better understood by examining how intelligence develops; learning and environment influence the process Jean Piaget s (1972) theory Stages of development: Sensorimotor Preoperational Concrete Formal operations Intellectual functions: Assimilation Accomodation 7 Ceci s (1990, 1993) bioecological model Intellectual abilities are highly influenced by context Information-Processing These models focus on how individuals process information Luria s (1966) theory Simultaneous processing Sequential processing Sternberg s (1985, 1988) triarchic theory Internal world of individual or mental processes that underlie intelligence Experiential subtheory Individual s contextual or external world 2
Individual s contextual or external world 8 Other Theories Gardner s (1993) theory of 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 1. Linguistic 2. Logical-mathematical 3. Musical 4. Spatial 5. Bodily-kinesthetic 6. Interpersonal 7. Intrapersonal 8. Naturalist 9. 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 Kaufman Instruments 10 11 Additonal Individual Instruments Wechsler Scales Wechsler Adult Intelligence Scale III (WAIS-III, 1997) Wechsler Intelligence Scale for Children IV (WISC-IV, 2003) Wechsler Preschool and Primary Scale of Intelligence III (WPPSI-III, 2002) Wechsler Memory Scale III (1997) WAIS-III Verbal IQ, Performance IQ, Full Scale IQ 3
1 WAIS-III Verbal IQ, Performance IQ, Full Scale IQ Composite Scores: Verbal Comprehension Index Perceptual Organization Index Working Memory Index Processing Speed Index 2 Uses basal and ceiling levels. Scales: Verbal Vocabulary Similarities Arithmetic Digit Span Information Comprehension Letter-Number Sequencing Performance Picture Completion Digit-Symbol Coding Block Design Matrix Reasoning Picture Arrangement Symbol Search Object Assembly 12 13 WISC-IV Full Scale IQ no longer use Verbal IQ and Performance IQ like earlier versions; now use Four Index Scores: 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 1. Fluid Reasoning 2. Knowledge 3.Quantitative Reasoning 4
2. Knowledge 3. Quantitative Reasoning 4. Visual-Spatial Processing 5. Working Memory 14 Basal level, ceiling level, routing test Kaufman Instruments Kaufman Assessment Battery for Children, Second Edition (KABC-II, 2004) Kaufman Adolescent and Adult Intelligence Test (KAIT, 1993) Not as widely used as Wechsler instruments 15 16 Integration of different theoretical approaches KABC-II Designed to assess children 3 to 18 Yields 4 or 5 scales depending on whether the Cattell-Horn- Carroll (CHC) or Luria approach is used CHC perspective; composite = Fluid-Crystallized Index Short-Term Memory Visual Processing Long-term Storage and Retrieval Fluid Reasoning Crystallized Abilities Luria perspective; global score = Mental Processing Index Sequential Processing Simultaneous Processing Learning Ability Planning Ability KAIT Designed for individuals 11-85 years 3 intelligence scales: Fluid (Gf) Crystallized (Gc) 5
Crystallized (Gc) Composite 17 6 subtests: 3 assess fluid intelligence 3 assess crystallized intelligence Additional Individual Instruments Differential Ability Scales-Second Edition (Elliot, 2006) Slossen Intelligence Test-Revised, Third Edition (Nicholson & Hibpshman, 1990) Raven s Standard Progressive Matrices (Raven, Court, & Raven, 1983) Peabody Picture Vocabulary Test III (Dunn & Dunn, 1997) 18 Test of Nonverbal Intelligence 3 (Brown, Sherbenou, & Johnsen, 1997) Group Intelligence Testing Given more often than individual intelligence tests, usually in schools Not as easy to monitor test-taker s behavior during assessment Require more reading than individual tests Must consider other factors of individual (culture, gender, background info, language proficiency) in interpreting results 19 Group Intelligence Testing (cont.) Cognitive Abilities Test (CogAT) Otis-Lennon School Ability Test, 8 th edition (OLSAT-8) Naglieri Nonverbal Ability Test (NNAT) 6
Multidimensional Aptitude Battery II (MAB-II) 20 Wonderlic Personnel Test (WPT) 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 21 Declines tend to occur in areas of fluid intelligence What Do Intelligence Scores Predict? Intelligence tests appear to be related to academic performance The relationships among IQ scores, occupational success, and income are not simple Validity generalization Refers to findings that the same test score data may be predictive for all jobs if a test is valid for a few occupations, the test is valid for all jobs in that cluster. GATB validity coefficients can be generalized to other occupations. Concerns regarding the use of the Job Family method and minority groups 22 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.50 Both genetic and environmental factors have significant 7
23 Both genetic and environmental factors have significant effects on intellectual development, with IQ scores seemingly to be related to the interaction between the two What Environmental Factors Influence Intelligence? Culture and language School attendance Other effects of schooling; quality of schools Family environment 24 25 Environmental toxins Are There Group Differences in Intelligence? 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, etc. What is the Flynn effect? James Flynn (1984, 1987) first to identify steadily increasing intelligence test scores in recent years Gains in IQ not reflected in gains in achievement Possible explanations: better nutrition, more test sophistication, changes in education and opportunities, changes in parenting practices 8