Intelligence: Overview & Psychometric Approach

1
Intelligence
Give a definition of intelligence that you could
defend, explaining why you believe you could
defend it. Give examples of ways your definition
of intelligence might be measured and skills
people might have who would do well on those
measures. Describe how you would differentiate
measures of intelligence from measures of
achievement.
2
Intelligence
Suppose you were asked to give a talk to parents
and educators on the topic Can IQ scores be
raised? You are asked to discuss both the
hereditarian and environmental aspects of the
issue. What would your arguments be for both a
strong hereditarian position AND a strong
environmentalist position? Be certain to give
specific suggestions from an environmental
perspective on how IQ could be raised.
Developed by W. Huitt, 1999
3
Definitions of Intelligence
Whatever intelligence tests measure
E. G. Boring
The global capacity of a person to act
purposefully, to think rationally, and to deal
effectively with his/her environment
D. Wechsler
Psychology textbooks
The general ability to perform cognitive tasks
Weschler, D. (1939). The measurement of adult
intelligence. Baltimore Williams Wilkins.
4
Definitions of Intelligence
Behaviorally-oriented definition
The capacity to learn from experience or the
capacity to adapt to one's environment
The cognitive ability to learn from experience,
to reason well, to remember important
information, and to cope with the demands of
daily living
R. Sternberg
Sternberg, R. (1988). The triarchic mind A new
theory of human intelligence. New York Viking.
5
Definitions of Intelligence
6
Approaches to Intelligence
Focus on the measurement of intelligence
Psychometric
Assumes normal distribution
Sternberg
Multiple Forms
Gardner
7
Approaches to Intelligence
Piaget
Developmental
Vygotsky
Brain metabolism
Brain/ neurophysiology
Brain imaging
8
Psychometric Approach
Based on an assumption of normal distribution
9
Psychometric Approach
Focus is on developing measures that predict
academic performance
Some researchers are critical of this approach
while others believe it has proven its correctness
Major issue What is it we want to know?

• Predict school success as presently structured

• Predict life success

• Develop human potential

10
Stability (Reliability) of IQ Scores
IQ measures fairly stable, especially after
adolescence

• r (age 6, age 18) .77

• r (age 12, age 18) .89

• r (averages 5, 6, 7 averages 17, 18) .86

• r (averages 11, 12, 13 averages 17, 18) .96

11
Predicting With IQ Measures (Validity)
IQ measures correlate with academic achievement
about r .5

• Persistence

• Interest in school

• Learning disabilities

• Encouragement from family, peers, teachers

• Other factors

12
Predicting With IQ Measures (Validity)
IQ measures correlate about the same or lower
with life success (Social status, Income)

• r (IQ, social status) .5

• r (IQ, income) .4

• Complex relationship because of impact of
  education

13
Predicting With IQ Measures (Validity)
Factors other than IQ account for more variance
when predicting life success (Goleman, 1995
Jencks, 1979)

• Affective/Emotional Factors

• Conative/Volitional Factors

Goleman, D. (1995). Emotional intelligence Why
it can matter more than IQ for character, health
and lifelong achievement. New York Bantam.
Jencks, C. (1979). Who gets ahead? The
determinants of economic success in America. New
York BasicBooks.
14
Issue of Nature vs. Nuture
What is the source of intelligence (as measured
by IQ)

• Nature (Biology, genetics)

• Nuture (Environment, family, schooling, changing
  economic conditions)

Correlations among various group members used to
test hypotheses
15
Issue of Nature vs. Nuture
16
Issue of Nature vs. Nuture
17
Issue of Nature vs. Nuture
Plomin et al. (1990) make the following estimates
.50

• Nature

• Within family

.25

• Between families

.15
.10

• Error

Plomin, R., DeFries, J., McClearn, S. (1990).
Behavioral genetics A primer (2nd ed.). New
York Freeman.
18
Nutures Influence
Stability of IQ measures true only if there are
no radical changes in the environment

• Gains in Appalachia in 1930s

• Venezuelan Intelligence Project (Herrnstein and
  others, 1986)

• Feuersteins (1980) Instrumental Enrichment

Feuerstein, R. (1980). Instrumental enrichment
An intervention program for cognitive
modifiability. Baltimore University Park Press.
Herrnstein, R., Nickerson, R., de Sanchez, M.,
Swets, J. (1986). Teaching thinking skills.
American Psychologist, 41, 1279-1289.
19
Nutures Influence

• Average gain about 3 points per decade

20
Nutures Influence
21
Nutures Influence

• Average gain about 3 points per decade

• 19-year-olds in Netherlands went up more than 8
  points from 1972-1982

22
Nutures Influence

• Daily life and occupational experiences more
  complex

• Better nutrition

• Measuring abstract problem solving ability,
  not really intelligence

23
Issue of Nature vs. Nuture
Issue of nature vs. nuture is especially critical
for educators

• If nature, our role is to sort and select

• If nuture, our role is to develop

24
Issue of Nature vs. Nuture
Of course, the reality is that both are important
25
Psychometric Approach
Because IQ is a reliable and valid predictor of
academic performance and academic performance is
related to SES, educators should look at methods
that have demonstrated an ability to impact IQ
Educators can also look to other theories of
intelligence for some ideas about human potential

• Sternberg

• Gardner

• Piaget

26
The End