Intelligence & Reasoning

1. Intelligence & Reasoning

2. Your Implicit Theories of Intelligence

3. 1986 Expert Definitions • Adaptation to environment • Basic mental processes • Reasoning, problem solving, decision making • Metacognition –

4. Intelligence Consider Albert Einstein (1879 - 1955) German-born U.S. physicist theory of general relativity exploitation of atomic energy won a Nobel prize in 1921 "einsteinium" named after

5. Einstein • How intelligent was Einstein? Estimated IQ = 160

6. Can you think of others thought to be intelligent? And why?

7. What is IQ? • An estimate of intellectual ability • Wechsler - "capacity of the individual to act purposefully, to think rationally, and to deal effectively with [the] environment“ • True IQ can not be known • It’s a quantification of a concept… • …except it’s an often misunderstood and misused concept

8. History of Intelligence Testing • Sir Francis Galton (1822-1911) • Cousin of Darwin • English Intellectual • Correlation coefficient • Eugenics – forbidding certain individuals to bear children, etc. • Pioneer in Intelligence • Invented first comprehensive test of intelligence (Adults)

9. Galton cont’d • Two general qualities distinguished individuals who were more intelligent from those less intelligent • Energy = speed or neural quickness • Sensitivity = sensory acuity or accuracy • Had people close their eyes and put objects that looked and felt the same in order based on weight. Similar for touch: wires of differing fineness, taste = salt, hearing = pitch, smell = different amounts of perfume. • Intelligence is _______________________

10. Alfred Binet (1857-1911) • Found that Galton's tasks did not discriminate between children and adults • His work represented the beginning of modern intellectual testing.

11. History of the Study of Intelligence • Binet and Simon (early 1900s) • Higher-Order Mental Abilities Central to Intelligence • Direction: knowing what has to be done and how it is accomplished. • Adaptation: task selection and monitoring. • Control: Ability to criticize one’s thoughts and actions: If you notice the sum is smaller than one of the numbers you realise you have to do it again.

12. History of the Study of Intelligence • Binet and Simon (early 1900s) • All forms of making judgments, decision-making, strategizing = executive functioning • Believed intelligence could be improved through instruction and practice

13. General Intelligence • Charles Spearman’s Psychometric Model (1904) • Developed a new set of tests and the statistical technique “factor analysis” to make sense of the results. It finds patterns of correlations among scores or measures of identify sets of underlying abilities. • FA finds patterns of correlations among scores • Identified two separate factors influencing performance on intelligence tests: • g = general intelligence • s = specific ability

14. Spearman’s Psychometric Model • g = general intelligence • Used to explain why most intelligence tests correlated with each other (ranging from 0.30 to 0.60) • Some common denominator = biologically based • s = specific ability • Used to explain why correlations were not perfect • Learned ability • Score is a combination of both g and s

15. Two Kinds of g (general intelligence) • Raymond Cattell (1971) – worked with Spearman and later modified Spearman’s theory to include two kinds of g: • Fluid Intelligence • Reason abstractly and think flexibly • Perceive relationships or differences • Peaks between 20-25 years of age and then declines • Crystallized Intelligence • Derived from previous experience • Accumulated knowledge (words, cultural practices) • Increases until age 50

16. Modern Intelligence Tests • Stanford-Binet Intelligence Test • Developed by Lewis Terman at Stanford in 1916 • Influenced by Binet & Simon • Grounded in competencies central to schooling • Identify body parts of a doll • Similarities and differences (how are a dog and a cat similar? different?) • Arithmetic word problems

17. Binet-based tests, cont’d Intelligence Quotient (IQ) Mental Age = match the individual’s test score to the age group whose average score was similar • e.g., Mental Age = 10 • any child whose score was similar to an average 10-year-old • Mental age/actual (chronological) age x 100 = IQ • E.g., 10/10 = 1 x 100 = 100 • E.g., 10/8 = 1.25 x 100 = 125 • An IQ of 100 is average for your age group • This concept of IQ is not bad for children, but…Absurd to say that a 20 year old who performs as well as a 60 year old has an IQ of 300.

18. Wechsler Scales • Developed by David Wechsler in 1930s • Kept term “IQ” but adapted the meaning to compare performance to the average person. • Verbal subtests: vocabulary, similarities, information, comprehension, digit span, letter-number sequencing, arithmetic • Performance subtests: block design, picture completion, picture arrangement, object assembly, matrix reasoning, digit-symbol coding, symbol search

19. Wechsler Scales • Standardized Scoring: • compare your score to those from a large sample of individuals of the same age • Mean = 100 • Standard deviation = 15 • We’ll see more on this later • WISC-III = ___________

20. David Weschler • Wechsler’s Innovations… a. based the scoring scheme on the normal distribution - discarded the idea of IQ based on mental age b. involve verbal and performance scales c. relied less on verbal ability than previous measures of intelligence

21. WAIS • Full Scale IQ • Verbal IQ • Performance IQ

22. WAIS-III Verbal Subtests • Information: • what is the capital of France? • Comprehension: • what should you do if you find a wallet on the street? • Arithmetic: • If you have 4 apples and eat 3 how many are left? • Similarities: • How are dog and cat alike? • Vocabulary: • define chair, asylum,etc

23. Digit span: • repeat number sequences in forward and reverse order • Letter-Number sequencing: • Repeat list of letters and numbers in chronological order WAIS-III Performance Subtests • Digit symbol: • copy designs associated with different numbers • Picture completion: • determine what is missing from a picture • Block design: • arrange blocks to match a picture

24. Picture arrangement: • arrange pictures so they tell a story • Object assembly: • put a puzzle together • Matrix Reasoning: • Determine what goes next in a pattern • Symbol Search: • Determine if the target symbols match any of the symbols in the search group

25. WAIS and Binet Tests • are individual tests • usually administered on an one to one basis Two pitfalls: • expensive to administer • time consuming to administer

26. Common Uses - Past • Binet - detection of mental deficiencies or giftedness in children and mentaldeficiencies in adults • Terman-______________________ • Wechsler- assess learning disabilities and neuropsychological evaluation

28. More on INTELLIGENCE to come later: but for now, let’s look at tests in general

29. Measures of psychological constructs: applications and strategies • What’s a psychological test? • Assesses of a sample of behaviour. Interpret it cautiously (do we know the test is valid? Can we infer from the sample to day-to-day reality?). • Best to use more than one test (increases reliability + trust in the result).

30. Ex: Applying to Grad School • graduate school criteria: GRE scores, references letters, statement of purpose, experience, publications, marks and personal interviews. Participation in an Honours program also important for Psychology. • Looking for more than high grades. • when assessing some psychological construct, use... • 1. • 2.

31. Assessing the person… Rare for students Publications Person Grades The higher the better Higher The Better GRE Magic Number 1800 (top score 2400) Recommendation Know referees Well… Letter of Intent Is it clear? Do they know what they want, and want to research?

32. Categories of other Psychological Tests Personality Mental Abilities Others?

33. Personality Tests Objective: Projective Minnesota Multiphasic Personality Inventory. Multiple scales with multiple items. Thematic Apperception Test – personality said to be revealed depending on stories told about pictures of ambiguous scenes.

34. Mental Abilities Tests • Mental ability tests 1) Intelligence test 2) Aptitude 3) Achievement tests

35. Mental Abilities Tests • intelligence tests are intended to measure general mental ability • aptitude tests are intended to measure specific types of mental abilities: _________________________? • achievement tests are intended to gauge a person's mastery and knowledge of various subjects: _______

36. What Makes a Test Good? • A Test Must Be: • Reliable • Valid • Reliable = consistent • Valid = measuring what it is suppose to measure

37. Reliability and Validity Target Practice …!

38. Reliability and Validity Reliable but not valid

39. Reliability and Validity Neither reliable nor valid

40. Reliability and Validity Reliable and valid

41. Definition of Reliability reliability = refers to test's precision, dependability, consistency A reliable test minimizes error and provides repeatable consistent results.

42. Classical Test Theory Observed score True ability Random error + =

43. Classical Test Theory • Suppose my true weight is 140 lbs • Suppose my scale is cheap (unreliable) • Assessed Weight • X = 135, 143, 141, 144 • E = -5, 3, 1, 4

44. Types of Reliability • Test-retest • Alternate Forms • Internal Consistency • Inter-rater

45. (1) Test-Retest Reliability • Administering the same test to the same set of examinees on two separate occasions.

46. Test-Retest Reliability Questionnaire (Completed 9/20) ___ I feel I do not have much proud of. ___ On the whole, I am satisfied with myself ___ I certainly feel useless at times ___ At times I think I am no good at all ___ I have a number of good qualities ___ I am able to do things as well as others Questionnaire (Completed 9/27) ___ I feel I do not have much proud of. ___ On the whole, I am satisfied with myself ___ I certainly feel useless at times ___ At times I think I am no good at all ___ I have a number of good qualities ___ I am able to do things as well as others 4 4 3 4 1 2 1 1 4 4 3 4

48. (2) Alternate Forms • Two versions of the same test with similar content. • Forms must be equal

49. (3) SPLIT HALF • Measures internal consistency. • Correlate two halves such as odd versus even items. • Works only for tests with homogeneous content Odd Even

50. (4) Interrater Reliability • Measures scorer or inter-rater reliability • Do different judges agree?