PSYC 1020H Chapter Notes - Chapter 9: Sat, Wechsler Adult Intelligence Scale, Stanford–Binet Intelligence Scales
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Chapter 9- Intelligence and Psychological Testing
Notes
Key Concepts in Psychological Testing
● A psychological test is a standardized measure of a sample of a person’s behaviour
● They’re used to measure individual differences that exist among people in abilities,
aptitudes, interests and aspects of personality
● Intelligence test measures geeral etal aility→ iteded to assess itelletual potetial
rather than previous learning or accumulated knowledge
● Aptitude tests are designed to measure potential more than knowledge, break mental
ability into separate components
● Aptitude tests assess specific types of mental abilities ex. Differential aptitude tests
assess verbal reasoning, numerical ability, abstract reasoning, perceptual speed and
accuracy, mechanical reasoning, space relationships, spelling and language usage
● Achievement tests gauge a person’s mastery and knowledge of various subjects such as
reading or history
Personality Tests
● Personality tests measure various aspects of personality, including motives, interests,
values and attitudes
● Standardization refers to the uniform procedures used in the administration and scoring
of a test
● Test norms provide information about where a score on a psychological test ranks in relation to
other sores o that test → psyhologial tests tell you ho you sore relatie to other people
● A percentile score indicates the percentage of people who score at or below the score
one has obtained ex. You take a 40 item assertiveness scale and you get a score of 26,
you indicated a preference for assertiveness for 26 questions. This places you in the
82nd percentile, you appear to be as assertive or more assertive than 82 percent of
the sample of people who provided the basis for test norms
Reliability
● Refers to the measurement consistency of a test (or of other kinds of measurement
techniques
● A correlation coefficient is a numerical index of the degree of relationship between two
variables ex. The closer the correlation comes to +1.00, the more reliable the test is
● In estimating test-retest reliability, the two variables that must be correlated are the two
sets of scores from the administrations of the test.
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Validity
● Refers to the ability of a test to measure what it was designed to measure
● It is also used to refer to the accuracy or usefulness of the inferences or decisions based
on a test ex. Border conception of validity highlights that a specific test might be valid for
one purpose like placing students in school, and invalid for another purpose like making
employment decisions for a particular occupation
● Content validity- refers to the degree to which the content of a test is representative of
the domain it’s supposed to cover
● Criterion-related validity: is estimated by correlating subject’s scores on a test with
their scores on an independent criterion (another measure) of the trait assessed by the
test ex. Let’s say you developed a test to measure aptitude for becoming an airplane
pilot. You could check its validity by correlating subjects’ scores on your aptitude test
with ratings of their performance in pilot training. If your test has reasonable validity there
is a strong correlation between the test and criterion measure
● Construct validity- the extent to which there is evidence that a test measures a
particular hypothetical construct ie. Intelligence, creativity, exraversion
Galton’s studies of Hereditary Genius
● Hypothesized that exceptionally bright people should exhibit exceptional sensory acuity
● Measured sensitivity to high pitched sounds, colour perception, and reaction time.
However, this was a failure has the research eventually showed that the sensory
processes that he measured were unrelated to other criteria of mental ability he was
trying to predict.
● Coined the phrase nature vs nuture to refer to heredity-environment issue
● Invented the concepts of correlation and percentile test scores
Binet-Simon Scale
● Expressed a child’s score in terms of mental level or mental age. A child’s mental age
indicated that he or she displayed the mental ability typical of a child with that
chronological (actual) age
Stanford Binet Intelligence Scale
Scale was expanded by Lewis Terman and colleagues at Stanford University
● An intelligence quotient (IQ) is a child’s mental age divided by chronological age
multiplied by 100
● This idea was suggested by William Stern
● Made it possible to compare children of different ages as it placed all children regardless
of age on the same scale, which was centred at 100 if their mental age corresponded to
their chronological age
Wechsler’s innovations
● Set out to improve on the measurement of intelligence in adults
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● He published the first high-quality IQ test designed specifically for adults, which came to
be known as the Wechsler Adult Intelligence Scale
● Made his scales less dependent on subject’s verbal ability than the Stanford-Binet
● Formalized the computation of separate scores for verbal IQ, performance IQ, and full
scale IQ
● Normal distribution
The Debate about the Structure of Intelligence
● Factor analysis: correlations among many variables are analyzed to identify closely
related clusters of variables > factor analysis helps us figure out the hidden factors
influencing those variables!
● Spearman used factor analysis to examine correlations among tests of many mental
abilities; believed they all shared g for general mental ability
● L.L Thurstone is an American psychologist who developed the Scholastic Aptitude Test
(SAT) he concluded that intelligence involves multiple abilities
● Seven independent factors called primary mental abilities: word fluency, verbal
compensation, spatial ability, perceptual speed, numerical ability, inductive reasoning
and memory
● For theoretical guidance they turned to a model of intelligence that proposed that g
should be divided into fluid intelligence and crystallized intelligence
● Fluid intelligence involves reasoning ability, memory capacity, and speed of information
processing. Crystallized intelligence involves ability to apply acquired knowledge and
skills in problem solving
What Do Modern IQ Scores Mean
● Normal distribution is a symmetric, bell-shaped curve that represents the pattern in
which many characteristics are dispersed in the population
● Deviation IQ scores locate subjects precisely within the normal distribution, using the
standard deviation as the unit of measurement
● For most IQ tests, the mean of the distribution is set at 100 and the standard deviation at
15
● Modern IQ scores indicate exactly where you fall in the normal distribution of intelligence
● Do intelligence tests have adequate reliability? Yes. Most IQ tests report commendable
reliability estimates. Range into the 0.90s
● Do intelligence tests have adequate validity? Yes but IQ test are valid measures of the
kind of intelligence necessary to do well in academic work but if the purpose is to test
intelligence in a broader sense, the validity of IQ tests is questionable
● Three basic components of intelligence: verbal, practical and social intelligence
● IQ scores tend to stabilize around the ages of 7-9, but meaningful changes are possible.
IQ scores are associated with occupational attainment and income, but the correlations
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Document Summary
A psychological test is a standardized measure of a sample of a person"s behaviour. They"re used to measure individual differences that exist among people in abilities, aptitudes, interests and aspects of personality. Intelligence test measures ge(cid:374)eral (cid:373)e(cid:374)tal a(cid:271)ility i(cid:374)te(cid:374)ded to assess i(cid:374)telle(cid:272)tual pote(cid:374)tial rather than previous learning or accumulated knowledge. Aptitude tests are designed to measure potential more than knowledge, break mental ability into separate components. Aptitude tests assess specific types of mental abilities ex. Differential aptitude tests assess verbal reasoning, numerical ability, abstract reasoning, perceptual speed and accuracy, mechanical reasoning, space relationships, spelling and language usage. Achievement tests gauge a person"s mastery and knowledge of various subjects such as reading or history. Personality tests measure various aspects of personality, including motives, interests, values and attitudes. Standardization refers to the uniform procedures used in the administration and scoring of a test.