Intelligence Testing

Transcription

1 Intelligence Testing

2 Intelligence Testing Play Pros and Cons of Intelligence Tests (6:29) Segment #17 from Psychology: The Human Experience.

3 Origins of Intelligence testing Intelligence Test a method of assessing an individual s mental aptitudes and comparing them to those of others, using numerical scores

4 Alfred Binet ( ) Developer of the first test to classify children s abilities using the concept of mental age Mental age The chronological age that corresponds to the difficulty of the questions a child can answer Child who does as well as the average 8-year-old is said to have a mental age of 8

5 Lewis Terman ( ) Adapted Binet s tests for use in the United States as the Stanford-Binet intelligence test The test reported intelligence as a calculated IQ score. Side note: Terman promoted use of intelligence testing to encourage or discourage people from reproducing

6 Intelligence Quotient (IQ) IQ = (MA/CA) X 100 On contemporary tests, the average performance for a given age is assigned a score of 100 Works great for children, but not for adults A 50 yr old does as well as a 25 yr old would have an IQ of 50? Technically there is no longer an intelligence quotient, but we still use the term IQ.

7 Assessing Intelligence Achievement Tests A test designed to assess what a person has learned Classroom test at the end of a unit Aptitude Tests A test designed to predict a person s future performance Aptitude is the capacity to learn o ACT and SAT

8 Assessing Intelligence David Wechsler ( ) Wechsler intelligence scales Wechsler Adult Intelligence Scale (WAIS) Wechsler Intelligence Scale for Children (WISC) WAIS (most widely used today) Includes 11 subtests Gives overall intelligence score, but also separate verbal and performance (nonverbal) scores

9 Assessing Intelligence: Sample items from the wais VERBAL General Information Similarities Arithmetic Reasoning Vocabulary Comprehension Digit Span PERFORMANCE Picture Completion Picture Arrangement Block Design Object Assembly Digit-Symbol Substitution From Thorndike and Hagen, 1977

10 How do we construct Intelligence tests? Tests must be: Standardized Reliable Valid

11 Assessing Intelligence Standardization Test must be pre-tested to a representative sample of people Form a normal distribution Normal Curve (Normal distribution/bell Curve) The symmetrical bell-shaped curve that describes the distribution of many physical and psychological attributes Most scores fall near the average, and fewer and fewer scores lie near the extremes

12 The Normal Curve

13 Performance on IQ scores has steadily increased over generations Known as the Flynn Effect Environmental factors? Reduction in malnutrition Access to schooling Technological advances

14 Reliability Assessing Intelligence The extent to which a test yields consistent results over time Assessed by consistency of scores on: Validity Two halves of the test (split-half) Alternate forms of a test Retesting The extent to which a test measures or predicts what it is supposed to

15 Assessing Intelligence Content Validity The extent to which a test samples the behavior of interest Driving test that samples driving tasks Criterion Behavior (such as college grades) that a test (such as the SAT) is designed to predict The measure used in defining whether the test has predictive validity

16 Assessing Intelligence Predictive Validity Success with which a test predicts the behavior it is designed to predict Assessed by computing the correlation between test scores and the criterion behavior Also called criterion-related validity

17 Brain Size and Intelligence Is there a link? Small +.15 correlation between head size and intelligence scores (relative to body size). Using an MRI we found +.44 correlation with brain size and IQ score.

18 Brain Function and intelligence Higher performing brains are less active than lower performing brains (use less glucose). Neurological speed is also a bit quicker.

19 does intelligence change over time? By age 3, a child s IQ can predict adolescent IQ scores. Depends on the type of intelligence, crystallized or fluid. (crystallized = concrete) (fluid = flexibility)

20 Extremes of intelligence Akrit Jaswal

21 Personality and Assessment

22 Psychodynamic and Humanistic Perspectives

23 Personality An individual s characteristic pattern of thinking, feeling, and acting

24 The Psychodynamic Perspective

25 Sigmund Freud ( ) Founder of psychoanalysis Proposed the first complete theory of personality A person s thoughts and behaviors emerge from tension generated by unconscious motives and unresolved childhood conflicts.

26 Psychodynamic Perspective A more modern view of personality that retains some aspects of Freudian theory but rejects other aspects Retains the importance of the unconscious mind Less emphasis on unresolved childhood conflicts

27 Psychoanalysis Freud s theory of personality Also a therapeutic technique that attempts to provide insight into one s thoughts and actions Does so by exposing and interpreting the underlying unconscious motives and conflicts

28 The Psychodynamic Perspective: Freud s View of the Mind

29 Free Association Freudian technique of exploring the unconscious mind by having the person relax and say whatever comes to mind no matter how trivial or embarrassing

30 Conscious Mind The thoughts and feelings one is currently aware of

31 Preconscious Mind A region of the mind holding information that is not conscious but is retrievable into conscious awareness Holds thoughts and memories not in one s current awareness but can easily be retrieved

32 Unconscious Mind A region of the mind that includes unacceptable thoughts, wishes, feelings, and memories