Intelligence Testing

1. Intelligence Testing Melissa Stern PSY 4930 October 3, 2006

2. What is Intelligence? • A loaded question . . . • Ability to modify one’s behavior to meet demands of the situation • Abstract reasoning (using symbols or mental representations) • Capacity to acquire knowledge • Problem solving ability

3. Definition of Intelligence Common to many definitions of intelligence • Knowledge-based thinking • Apprehension • Adaptive purposeful striving • Fluid analytic reasoning • Mental playfulness • Idiosyncratic learning

4. Theories of Intelligence • Terman coined the term “Intelligence Quotient” (IQ) in 1916 • Mental age/Chronological age • Spearman’s 2 Factor Theory (1927) • Intelligence = • General factors (g) — “mental energy” • E.g., abstract reasoning, problem solving • Specific factors (s) — less complex tasks • E.g., motor speed, attention, v-m coordination, memory • Although originally a 2 factor theory, g is the only factor that accounts for correlations among intellectual abilities

5. Theories of Intelligence • Thurstone’s Multidimensional Theory (1938) • Eight primary mental factors • Verbal, perceptual speed, inductive reasoning, number, rote memory, deductive reasoning, word fluency, space or visualization) • He eventually found that these factors correlated and later postulated a second-order factor similar to “g”

6. Multiple Intelligences? MUSICAL INTELLIGENCE Is it a type of an intelligence? Or is it just special talents? Discuss!

7. Theories of Intelligence • Cattell & Horn’s Fluid and Crystallized Intelligence (1966) • Fluid intelligence=one’s inborn abilities largely determined by genetics and biology • Fluid intelligence develops through childhood and adolescents • Examples: number/letter series, matrices • Crystallized Intelligence=acquired skills and knowledge • Influenced by environment and culture • Continues to develop over the lifespan • Examples: vocabulary, general information • Some tasks measure both: • Arithmetic reasoning

8. Theories of Intelligence • Piaget’s Developmental Theory • Hierarchical model with four major periods of cognitive development • Sensorimotor period • Preoperational period • Concrete operations period • Formal operations period • Correlations have been found between Piagetian tasks and psychometric scales of intelligence

9. A Modern View of Intelligence • Intelligence is an integrated construct including: • Biological—dependent on genetics, brain structure, physiological functioning of brain • Cognitive—metacognition and ordinary cognition • Motivational—magnitude, direction, and disposition of individual • Behavioral—behavior in academic, social, and adaptive domains • Genetically-determined intelligence is always modified by experience

10. Environmental Influences on IQ • Factors that enhance IQ: • Stimulating environment • Good medical care/nutrition • Parental involvement in learning • Rich language environment • Factors that negatively impact IQ: • Persistent poverty • Perinatal complications, inadequate stimulation in environment, lead exposure • Large family size • Nutrition during gestation and early childhood

11. Heredity and IQ • “Heredity may limit a child’s potential, but environment permits their potential to be actualized” (Sattler, 2001, p. 180) • We inherit genes, not an actual IQ • Genetics is only 1 factor affecting IQ (familial, educational, nonfamilial factors) • IQ can change, but it is difficult • Does seem to go up on average about 4 points between childhood and adolescence (develop problem-solving strategies over time)

12. The Bell Curve (1994) • Controversial book on the social ramifications of IQ stratification • The “Cognitive Elite” associate with other elite • Physical separation from others • Make more money • Live in different neighborhoods

13. The Bell Curve: Social Problems and IQ • Poverty -  IQ predicts poverty, even more than SES in which people grow up • Schooling -  IQ increases risk of dropping out of school and decreases chances of college degree • Unemployment, Idleness and Injury -  IQ is associated with unemployment, frequent injury, or idleness (removing oneself from the workforce)  • Family -  IQ is related to high rates of divorce, lower rates of marriage, and higher rates of illegitimate births 

14. The Bell Curve: Social Problems & IQ • Welfare Dependency -  IQ increases the chances of chronic welfare dependency  • Parenting -  IQ of mothers correlates with low birth weight babies, poor child motor skills and social development, and children’s behavioral problems  • Crime -  IQ increases the risk of criminal behavior • Civility and Citizenship – those with  IQ vote least often

15. The Bell Curve: Gender, Ethnicity & IQ • Few gender differences were found • Males higher on spatial and quantitative • Females higher on verbal ability • East Asians score highest, then European Americans, Hispanics, and African Americans • APA task force on IQ • IQ can predict individual differences, but not necessarily group differences • Socioeconomic influences may play a role • Cultural differences may affect education • emphasis on spirituality, harmony, movement, verve, affect, expressive individualism, communalism, etc.

16. IQ Tests and Culture • Culturally Biased • Proponents of this view feel IQ tests are biased against ethnic minorities and don’t take their sociocultural factors into account • Culturally loaded • Proponents of this view feel IQ tests are reflective of the knowledge and skills of the dominant society (those who created the test)

17. Pros and Cons of IQ Testing

18. Common IQ Misperceptions • IQ is innate • IQ never changes • IQ tests provide perfectly reliable scores • All IQ tests measure the same thing • IQ test scores are interchangeable

19. IQ tests vs. Achievement tests • IQ tests measure broader abilities • IQ tests are more predictive of future performance • Achievement tests (reading, math, etc.) are heavily dependent on formal learning at home or school • Achievement test scores change more readily • Achievement tests assess mastery of factual information; IQ tests assess ability to apply information in new ways

20. Common Intelligence Tests • Stanford-Binet Intelligence Scale • Originally developed in 1916 • Currently in the 4th edition • Wechsler Intelligence Scale (WISC) • For children 6-16 years • Currently in the 4th edition (2003) • Wechsler Preschool and Primary Scale of Intelligence (WPPSI) • For children 3 years to 7 years, 3 months • Bayley Scales of Infant Development (BSID) • For children aged 1 to 42 months • Cognitive, Motor, and Behavioral scales

21. IQ Test example: WISC-IV • 15 subtests (some of them are optional) • Administration time varies from 1-3 hours • Must be trained in order to administer – complicated rules • Provides • Full Scale IQ--Global estimate of child’s general intellectual capacity/potential/level of cognitive ability and the relative standing compared to the normative population • Verbal Comprehension Index –verbal reasoning skills • Perceptual Reasoning Index – nonverbal reasoning skills • Working Memory –ability to attend to and hold information in memory to formulate responses • Processing Speed – speed of processing information • Uses the deviation IQ (mean = 100, SD = 15)

22. WISC-IV Subtests • Block Design • Similarities • Digit Span • Picture Concepts • Coding • Vocabulary • Letter-Number Sequencing • Matrix Reasoning • Comprehension • Symbol Search • (Picture Completion) • (Cancellation) • (Information) • (Arithmetic) • (Word Reasoning)

23. Matrix Reasoning Example

24. VCI Similarities Vocabulary Comprehension Information* Word Reasoning* PRI Block Design Picture Concepts Matrix Reasoning Picture Completion* WMI Digit Span Letter-Number Sequencing Arithmetic* PSI Coding Symbol Search Cancellation* WISC-III Subtests

25. IQ Testing Considerations • Examiner variability (i.e., giving extra help, errors in administration, incorrect scoring, etc.) • Situational variability (i.e., on/off medications, Ritalin, fatigue, illness, hunger, etc.) • Individual subtest scores are not as reliable as the FSIQ and Indices • Qualitative observations are also important

26. Ratio IQ First type of IQ Stern (1938) IQ = MA/CA x 100 Same IQ has different meanings at different ages Not used as often now Deviation IQ A type of standard score Mean = 100, SD = 15/16 Compares IQ to same age peers Normal distribution WISC uses this Types of IQ