Intelligence and the Assessment of Intelligence

1. Intelligence and the Assessment of Intelligence

2. Francis Galton • Father of the study of individual differences

3. Early History of Testing • Father of IQ testing • Intelligence test: quantification of mental functioning • Binet Scale: first intelligence test • Developed concept of mental age • Viewed intelligence as malleable

5. Testing Moves to the United States: Henry Goddard • Translated Binet scales for Vineland residents • Widely distributed the Binet Scale

7. Testing in the United States: Lewis Terman Revised Binet’s Scales: • Adapted items for U.S. • Added new items • Established new age norms • Extended the upper age limit • Adopted idea of IQ quotient Resulting Scale: Stanford-Binet Scale

8. Intelligence Quotient • IQ= Mental age/Chronological Age X 100 • IQ ratio enables direct comparison of children of different ages

9. Changes in Conceptualizations of Intelligence: Binet - Terman • Binet: intelligence malleable • Goddard and Terman: intelligence is inherited and stable

12. William Stern • Developed the IQ quotient that was adopted by Terman

13. Robert Yerkes • Developed group intelligence test to assess army recruits • Results used to screen, classify, and assign

14. Members of the Committee on the PsychologicalExamination of Recruits

15. David Wechsler • Designed Wechsler scales • Measures of verbal and nonverbal abilities

16. The Wechsler Scales • Wechsler Intelligence Scale for Children (WISC-R) • Wechsler Adult Intelligence Scale (WAIS) • Wechsler Preschool and Primary Scale of Intelligence (WPPSI)

17. Charles Spearman From emphasis on testing to emphasis on understanding intelligence • G Factor (general ability)

18. L.L. Thurstone • Accepted the hypothesis of a general factor • Disputed the importance of the g factor • Identified 7 primary mental abilities

19. Raymond Catell • Suggested that “G” had two components: fluid and crystallized intelligence • Fluid: primary reasonability ability • Crystallized: acquired knowledge

20. Guildford • Parted with the notion of a general factor • Proposed that intelligence is comprised of many (120) separate abilities

21. Gardner Proposed a theory of multiple intelligences: • Linguistic • Musical • Logical-mathematical • Spatial • Bodily kinesthetic • Personal

22. Sternberg Triarchic theory of intelligence: • Academic • Practical • Creative

23. Developmental Conceptualization of IQ: Jean Piaget • Cognitive abilities develop through an interaction of developing brain and child’s experiences

24. Stages of Cognitive Development • Sensorimotor (Birth to 2 years) • Preoperational (2-7years) • Concrete operations (7-11 years) • Formal Operations (11 years to adulthood)

25. Sensorimotor Period The Infant’s major cognitive tasks centers around: • Sensations: seeing and hearing • Motor activities: kicking, sucking, and reaching Object permanence is acquired at the end of this stage

26. Preoperational Period • Development of language • Egocentrism

27. Concrete Operational Period • Conservation • Increased logical thinking

28. Formal Operational Period • Abstract reasoning • Form and test hypotheses

29. Cognitive Development • See video demonstrating the four stages of cognitive development

30. Current Intelligence Testing • Despite changes in conceptualization of intelligence from one factor to multiple factors, current IQ tests have not outgrown the G factor of Spearman • The IQ score, which is still widely used, implies an assessment of general ability.

31. Verbal Subtests Information Vocabulary Arithmetic Similarities Comprehension Digit Span Performance Subtests Picture Completion Picture Arrangement Block Design Object Assembly Digit Symbol The Wechsler Scales

32. Verbal Subtests • Information: culturally acquired info • Vocabulary: general verbal intell. • Arithmetic: numerical reasoning • Similarities: abstract reasoning • Comprehension: social norms • Digit Span: short term memory

33. Performance Subtests • Picture Completion: visual concentration and nonverbal general information • Picture Arrangement: ability to plan, interpret and anticipate in social context • Block Design: perceptual organization, spatial visualization and abstract concentration • Object Assembly: visual motor organ., synthesis • Digit Symbol: visual memory

35. Similarities • In what way are an orange and a banana alike?

36. Vocabulary • Bed • Ship • Penny

37. Digit Span • Demonstrate

38. Picture Completion

39. Block Design

40. Object Assembly

41. Digit Symbol Coding

42. Picture Arrangement

43. Wechsler Scales: Clinical Use • Estimation of general intelligence (correlates with academic success and occupational status) • Examine the discrepancy in performance between verbal and performance subtests • Examine the variability among subtests

44. Controversies: Race and IQ Average IQ score differ for various racial and ethnic groups • Asian Americans • Whites • Latina • African Americans

47. Race and IQ Controversy: Key Figures Genetics • Goddard • Pearson • Terman • Jensen: Harvard Educational Review • Hernstein and Murray: Under the Bell Curve • Shockley

48. Aruther Jensen “Those who would accord any treatment to individuals solely by virtue of their race will find no rational support in any of the scientific findings from psychological testing or present day theories of differential psychology.” William Shockely “Nature has color coded groups of individuals so that statistically reliable predictions of their adaptability to intellectually rewarding and effective lives can easily be made and profitablybe used by the pragmatic man-in-the-street.”

49. Explanations of Ethnic Differences in IQ Scores • Tests are not valid • Economics • Genetics** **Most controversial

50. Genetics Heritability estimates for IQ is about .50 in a population Environment Like other traits, IQ is changeable (height for example). Educational experiences affect IQ IQ scores have increased over the years (nutritional factors, increasing access to information) Genetics