1.
2.
Intelligence and Psychological Testing
What is Intelligence?
a. Intelligence
i.
Verbal ability, problem-solving skills, and the ability to
adapt to and learn from everyday experiences.
b. Individual differences
i.
The stable, consistent ways in which people are different
from each other.
c. Issues
i.
Measurement
ii.
General trait vs. specific skills
iii.
Process vs. product (Skill vs. knowledge?)
iv.
Nature vs. nurture
v.
Aptitude and achievement tests
3.
The Development of The IQ Test
a. Sir Francis Galton
b. Alfred Binet and Theodore Simon
c. Henry Goddard
d. Lewis Terman
e. David Wechsler
4.
Early History
a. Sir Francis Galton (1822-1911)
i.
English scientist and cousin of Darwin.
(1) Hereditary Genius (1869)
(a)
presented evidence that talent is inherited
(b)
Led him to found the EUGENICS movement.
ii.
His system of classifying fingerprints is still in use.
b. Alfred Binet (1857-1911) and Theodore Simon(1873-1961)
(1) Binet-Simon Intelligence Scale(1905)
(a)
(b)
(c)
Used the empirical test-development method.
Develop items that correlate with typical
performance at each age.
Mental age
c. Henry Goddard (1866-1957)
i.
Built tests to spot “mentally defective” immigrants
ii.
Immigration quotas and legalized involuntary sterilization
have been defended with inaccurate intelligence test results.
5.
Lewis Terman (1877-1956)
a. Saw intelligence as a fixed, inherited property.
b. Stanford-Binet Intelligence Scale (mid-1900s)
i.
Created a paper and pencil version
6.
ii.
Adopted Stern’s IQ formula
David Wechsler (1896-1981)
a. Wechsler Adult Intelligence Scale
i.
Six performance subscores (PIQ)
ii.
Five verbal subscores (VIQ)
iii.
Full-scale IQ
b. Also created the WISC, WPPSI, WMS
7.
Key Concepts in Measurement
a. Reliability
b. Validity
c. Standardization
8.
Reliability
a. Consistency of measurements
i.
ii.
Is the test dependable?
A measure should give the same score each time the same
person takes it
b. Types of Reliability
9.
i.
Test-retest reliability
(1) Does it give the same result when used again?
ii.
Alternate forms reliability
(1) Do other versions give the same results?.
iii.
Split-half reliability
(1) Do the two halves give the same results?
Correlation and Reliability
a. Reliability is measured as a correlation. Most reliability
coefficients for psychological tests fall between 70 and .95.
10.
Test-Retest Reliability
a. Scores on the first testing are shown on the left, and scores on a
second testing a few weeks later are on the right.
i.
If subjects obtain similar scores on both tests the testretest reliability.
11.
Validity
a. The meaning of the measurements
i.
Criterion-related validity
ii.
Construct validity
iii.
Content validity
12.
Criterion-Related Validity
a. The validity of a pilot aptitude is supported if a high correlation is
found between test scores and ratings of their performance in a
pilot training program.
13.
Construct Validity
a. Psychologists evaluate a scale's construct validity by studying how
scores on the scale correlate with a variety of measures related to
the concept.
14.
Content Validity
a. Expert judgement.
b. Does the test cover the material?
15.
Standardization
a. Constant measurement conditions.
i.
Do you give the test the same way each time?
b. Comparison with a known sample.
i.
Against whom am I compared?
c. Test norms
i.
Average score for a designated group of people
ii.
Standardization group
iii.
Standards of performance for a test
16.
The Distribution of IQ
a. Mean
(1) (X)/N, by definition it is 100
b. Standard deviation
(1) Mean  1 68% of all scores 85-115
(2) Mean  2 95% of all scores 70-130
(3) Mean  3 99.5% of all scores 55-145
17.
a.
b.
c.
d.
18.
a.
19.
Issues
Prediction
Stability
Culture
Nature-Nurture
Prediction
What do they predict?
i.
School
ii.
Verbal/Quantitative vocations
Ontogenetic Stability
a. Correlation depends on age and lag
b. High correlations if
i.
Measurements are close together
ii.
Measurements are made when older
c. Studies
i.
Berkeley Growth Study
ii.
Fels Longitudinal Study
20.
Culture
a. IQ tests are culture specific
b. Eastern cultures value effort
21.
Intelligence: Heredity or Environment?
a. Heredity
i.
Family and twin studies
ii.
Heritability estimates
b. Environment
i.
Adoption studies
ii.
Cumulative deprivation hypothesis
iii.
The Flynn effect
c. Interaction
i.
The concept of the reaction range
22.
The Nature Argument
a. Francis Galton (1869)
(1) Believed that intelligence is genetic
(2) Determined by physical and perceptual attributes.
b. The Modern Version
i.
Concordance rate – identical > fraternal twins.
ii.
Correlation of separated identical twins is high.
iii.
Cyril Burt
(1) Used fraudulent data to argue that IQ is innate.
iv.
Arthur Jensen
(1) Claimed a heritability estimate of 80%
(2) But he relied on some of Burt’s work.
23.
Kinship Studies
a. Studies of IQ similarity.
i.
The graph shows mean correlations of IQ scores for
people of various family relationships.
24.
Heritability
a. A heritability ratio is an estimate of the portion of variation in a
trait determined by heredity.
25.
Reaction Range
a. Heredity sets limits on potential while the quality of the
environment influences where one scores within this range.
i.
ii.
Genetic limits on IQ can be inferred only indirectly.
One cannot know whether reaction ranges are narrow
(Ted) or wide (Chris).
26.
Kamin's Analogy
a. Between-group differences on a trait (the height of corn) could be
due to environment, even if heritability is high.
i.
The same reasoning presumably applies to ethnic group
differences in the trait of human intelligence.
27.
The Nurture Argument
a. Alfred Binet and Theodore (Theophile) Simon (1904)
(1) Binet held the conviction that intellectual levels could
change over time.
b. Intelligence may be affected by nutrition, health, an intellectually
stimulating and emotionally secure home, and appropriate rewards
for academic accomplishments.
i.
The rational for Project Head Start.
c. Scarr and Weinberg
i.
Report that adopted children have a higher IQ (106) than
nonadopted children.
d. The Environment?
i.
Increasing IQ scores over time (last 75 years)?
ii.
http://pespmc1.vub.ac.be/FLYNNEFF.html
e. Cultural Fairness
i.
Do you speak the “language?”
ii.
Do you have anything like the same culture?
28.
Culture: Development in Context
a. What is intelligence, anyway?
b. Cross- cultural research
i.
29.
Asian Americans' Academic Success
a. On many measures of educational success, the performance of
Asian American students exceeds that of other US ethnic groups.
i.
Most theorists believe that cultural factors are responsible
for Asian Americans' academic prowess.
30.
a.
b.
c.
d.
e.
31.
a.
b.
c.
32.
a.
b.
c.
d.
33.
Stevenson and Asian culture
Diversity
Creativity
Giftedness
Mental Retardation
Learning Disabilities
Savants
Creativity
What is creativity?
(1) Ability to think about a problem in novel and unusual
ways and to produce unique solutions that are valued.
(2) Creativity is domain specific.
(3) Thomas Edison
(a)
Genius is 1% inspiration and 99% perspiration.
Convergent thinking
(1) Produces one correct answer
(2) Type of thinking required on conventional intelligence
tests
Divergent thinking
(1) Thinking that produces many answers to a questions
(2) One characteristic of creativity
Live a More Creative Life
Try to be surprised by something every day
Try to surprise at least one person every day
Write down each day what surprised you and how you surprised
others
When something sparks your interest, follow it
Giftedness
a. Giftedness
i.
Well above-average intelligence (an IQ of 130 or higher).
ii.
A superior skill at something.
b. Characteristics of gifted children (esp. child prodigies)
i.
Precocity
ii.
A passion to master
iii.
Marching to their own drummer
34.
Mental Retardation
a. Mental retardation
(1) Diminished mental ability (IQ below 70)
(2) Diminished adaptive functioning (Vineland).
(3) Onset of these characteristics by age 18
b. Organic retardation
i.
Caused by a genetic disorder or brain damage
ii.
Cultural-family retardation
(1) No evidence of organic brain damage can be found
(2) IQ's range from 55-70
35.
Prevalence and Severity of Mental Retardation
36.
Learning Disabilities
a. A specific deficit in a child with otherwise normal intelligence
(IQ).
37.
Savants
a. Rare
i.
People with autism have some incredible mental ability.
b. The Case of Carl
(1) Did calendar calculating: named the weekday for any date.
c. The Twins: George and Charles
(1) Calendar calculators and good with numbers.
d. The Case of K.
(1) Memorized huge amounts of trivia with near perfect
recall.
e. The Case of Blind Tom
(1) Could play thousands of pieces of music on the piano,
perfectly, after merely hearing each piece played once.
38.
Some Views of Intelligence
a. The psychometric approaches
b. Sternberg’s Triarchic Theory
c. Gardner's Theory
39.
The Psychometric Approaches
a. Measurement (testing) based
i.
Emphasizes the products of intelligence
(1) Knowledge
b. Early Psychometricians
i.
Spearman
ii.
Thurstone's primary mental abilities
40.
Spearman
a. IQ = g + s +s +...+
i.
g = general
ii.
s = specific or skill (learned)
1
41.
s.n.
Thurstone's Primary Mental Abilities
a. Factor analysis revealed specific skills
i.
42.
a.
43.
2
Perceptual speed, numerical ability, word fluency, verbal
comprehension, space visualization, associative memory,
reasoning
Guilford's Model
In contrast to Spearman, J. P. Guilford concluded that intelligence
is made up of many separate abilities.
Sternberg’s Triarchic Theory
a. Focus
i.
Speed of processing
ii.
Type of processing
b. Componential
i.
Like conventional views
c. Contextual
i.
“Street smarts”
d. Experiential
i.
Two-facet
(1) Process novelty
(2) Automatize
44.
Gardner's Theory: Multiple Intelligences
a. Specific independent intelligences
b. Data sources
(1) Normal development
(2) Stroke and TBI patients
(3) Child prodigies
(4) “Savants”