Mental Abilities

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Mental Abilities Intelligence
Capacity to reason, remember, understand, solve
problems, make decisions
Grades, GPA, IQ, SAT score, GRE score,
creativity common sense or book smarts
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Measuring the Quality of tests
Reliability - results must be repeatable or stable

• Typically measured using a correlation
  coefficient
• test-retest give the same test twice
• alternate forms equivalent test
• split-half comparison between 2 equivalent
  portions

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Measuring the Quality of tests
Validity - degree to which it measures what it is
supposed to measure
Content Validity test content is related to
what it is supposed to measure
Criterion Validity test scores correlate with
another direct or independent measure of what
the test is supposed to assess
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Brief History of Intelligence Testing
1904 - Binet develops a set of intellectual tests
to identify children in need (age-graded)
1916 - Terman translates Binets test and puts it
to use, defining average intelligence as a
score of 100
1917 - Goddard used Binets test to identify
mentally deficient immigrants 83 Jews, 80
Hungarians, 87 Russians, 79 Italians
1920s - Government used alpha and beta
intelligence tests
1939 - Wechsler improved upon these tests
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WAIS - Verbal Subtest Examples
Comprehension What does this saying mean, A
rolling stone gathers no moss? Arithmetic A
boy ran 50 yards in 10 seconds. How many yards
did he run per second? Similarities How are
fast and slow alike? Digit Span Repeat the
following numbers backward 8-4-2-1-9
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WAIS - Performance Subtest Examples
Wade and Tavris (2000), Psychology 5th Ed.,
Prentice Hall, p.327.
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1. Water lilies double in area every 24 hours.
At the begin- ning of the
summer, there is one water lily on a lake. It
takes 60 days for the lake to become covered
with water lilies. On what day is the lake
half-covered?
2. A farmer has 17 sheep. All but 9 break
through a hole in the fence and wander away.
How many are left?
3. If you have black socks and brown socks in
your drawer, mixed in a ratio of 45, how many
socks will you have to take out in order to have
a pair of the same color?
4. With a 7-minute hourglass, and an 11-minute
hourglass, how can your time the boiling of an
egg for 15 minutes?
5. Washington is to one as Lincoln is to a.
Five b. Ten c. Fifteen d. Fifty
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Normative IQ distribution
Wade and Tavris (2000), Psychology 5th Ed.,
Prentice Hall, p.326.
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Cultural Difference in IQ scores
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How much of our intelligence is determined by
genetics/heredity? How much of our intelligence
is determined by our environment?
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Triarchic Theory of Intelligence
Analytic
Combination is Intelligence
Practical
Traditional IQ test, math problems
What response to make in a given circumstance
Creative
Musical, artistic
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Multiple Intelligence Gardner (1993)

• linguistic intelligence
• logical-mathematical intelligence
• spatial intelligence
• musical intelligence
• body-kinesthetic intelligence
• intrapersonal intelligence
• interpersonal intelligence
• naturalistic intelligence