PSY 3044 - Experimental Psychology                                                                  Christine Ruva

 

Discovering Psychology: Testing & Intelligence

 

 

I.       PSYCHOMETRICS: mental testing

A.     Cognitive Tests: measure various aspects of your mental abilities (e.g., intelligence and IQ tests, academic abilities and SAT).

B.     Personality Tests: measure noncognitive aspects of personality (e.g., interests, values, and personality traits).

 

ii.     intelligence

        A. The History Of Intelligence Testing           

                  1.       Sir Frances Galton (1822-1911): tried to establish the hereditary basis of intelligence.

a.        He believed that highly successful people perceive the world more accurately than less successful people.  Therefore, the eyesight of successful people should be keener and their reactions quicker than less successful people.  The results of his studies did not support this hypothesis.

2.      Alfred Binet (1857-1911) & Theophile Simon: In 1905 they produced the 1st workable intelligence test

a.      purpose: To measure the intellectual performance of school children so that teachers could separate and classify mentally retarded children from normal children and so that slower learners could get special classes (Public School System).  Testing was meant to replace subjective evaluations of teachers with objective evaluations.

b.      Binet believed that his test did not measure innate intelligence and that the test results should only be used to identify those areas in which children needed special help.

c.      Quantification of student performance via norms (the average score for an age group).  Each child’s score could then be compared to the norm for various age groups to determine his/her mental age.

                   3.       The Stanford‑Binet Intelligence Scale

a.      Lewis Terman (1877-1957): revised the Binet-Simon Scale and developed the intelligence quotient (IQ) an extension of work done by William Stern.

IQ = (Mental Age ¸ Chronological Age) x 100

4.      The Wechsler Scales: intelligence tests for adults and added nonverbal sections to IQ tests for younger children and people whose verbal abilities (English) are limited  (David Wechsler)

                           a. WIPPSI, WISC, WAIS

 

        B. Principles Of Psychological Tests

1.      Reliability: consistency of the measuring instrument

a. Test‑retest, alternate forms are examples

2.      Validity: Degree to which the test measures what it purports to measure.

a.      Construct validity – is the variable as we our measuring it a good representation of            the construct of interest.

b.      Predictive validity – does it adequately predict performance in the area alleged (e.g., SAT ® GPA, police employment exam ® performance as an officer)

3.      Standardization:  Administration is the same across groups, settings, times.

a.      Norms should be based on the population for which the test will be used later on (generalizability). 

b.      Norms provide a reference for interpretation of an individual’s score on a test.

c.      Normal curve describes Population distribution

 

 

C.     Kinds Of Intelligence: Intelligence as a multidimensional construct

 1.     Spearman's Model 

         a.        General intelligence (g), some specific abilities (s)

2.      Sternberg's model

a.      Triarchic theory of intelligence (see text book)

(1)     Analytical intelligence

(2)     Creative intelligence

(3)     Practical intelligence – the ability to adapt to existing environments: (1) ability to go into a new environment and learn what you need to know in it and then work effectively, (2) ability to change environment to make more suitable for your abilities, interests, and needs, and (3) ability to select a new environment.

a.      Prediction level of traditional IQ test for practical or real world intelligence is low.

3.      Gardner's multiple intelligences

a.      Seven distinct kinds of intelligence are proposed (see textbook)

 

D.     Misuse Of Intelligence Tests (see text)

1.      Eugenics, immigrant testing, labeling reflects negligent use of tests

 

E.      Hereditary And Environmental Determinants Of Intelligence

1. Hereditary determinants

a. Heritability estimates of intelligence range from 50 to 80 percent

b. Identical and fraternal twins, adoptees used to study this issue

2. Environmental determinants of intelligence

a.      Environmental stimulation contributes to intellectual performance

 

F.      Neuropsychological Test Of Intelligence

1.      Measure brain response as it adjusts to interruptions by sudden stimuli using EEG recordings.

2.      Certain brain waves (P300) are particularly sensitive to these interruptions.

3.      Theory: The brain in more intelligent people will have smaller P300 waves over time because it adjusts faster to the interruptions and absorbs new inputs more readily.

4.      This theory is related to another theory regarding the rate of habituation in young infants.

 

G.     Explaining Differences In Intelligence Tests Scores

1.      Richard Lewontin (1976): If we take a bag of seeds and plant half in fertile soil and the other half in barren soil what can we conclude about differences that occur within and between groups?  The difference among seeds within a each group may be due to heredity, but the average difference between the two groups reflects environmental factors.

2.      Are the tests biased?  That is, do the tests tell us that a person is not capable of doing something (e.g., earn a college degree) when in fact he/she is capable?

3.      Cultural biases:

a.      Overvalue some attributes (e.g., verbal ability and social conformity) and undervalue others (e.g., creativity and common sense)

b.      Test developed on white children and adults, but used to test all people.

4.      Steele & Aronson (1995): Some groups of individuals (e.g., African Americans and women) have the added pressure that poor performance can be interpreted as confirmation of negative stereotypes about that group.