Lecture overview
• Review of decisions made on Thursday
• Brief discussion of exams
• Gardner’s view of intelligence (will encounter this again later); other
views of intelligence (Sternberg; g)
• Early intelligence tests: Binet, Simon
• The IQ concept: Terman and the Stanford-Binet
• Wechsler and the WAIS
• Use of WAIS-R in sample intellectual assessment
• Problems with the IQ concept
• Individual differences in intelligence: genes or environment?
– Contribution of twin and adoption studies—'range of reaction' concept
– Environmental factors influencing intelligence
• Extreme intelligence: high IQs, genius and creativity
• Guided video
• QUIZ (2) – Outline & Chapter 9
Decisions made last class
• I will post my Powerpoints after each class.
• The guided video questions will be available on the website
before class; answers will be posted after class.
• On exam days, class will start at 10:00 instead of 9:30.
• After each exam, we will have optional “research day”
lectures. These lectures will present recently published
articles relevant to a few topics from that week’s lectures.
These “research days” are optional, and the material
discussed will not be on any exams – it is a chance to
explore further interests you may have.
Intelligence
• What is intelligence?
• Defining and measuring intelligence has been one of the
primary goals of psychologists over the last 100 years.
• Intelligence: (modern definition, text p.340)
“An internal capacity hypothesized to explain people’s abilities to:
– Solve problems
– Learn new material
– Adapt to new situations
– … differs across individuals… some people are better at these
tasks than other people.”
Original conceptions of intelligence:
A brief history
• Galton: took a variety of measures of individual differences (each
person has their own unique set of characteristics). Range of abilities
tested – but were poor predictors of intellectual performance and
academic success
• Spearman’s g:
– Used factor analysis to group results on a variety of mental tests.
– Results on individual tests was called specific factor, s
– General factor underlying overall performance called g or general intelligence
• Fluid and crystallized intelligence
– Two dimensions of general intelligence:
• Fluid is basic ability (problem solving, reasoning)
• Crystallized is knowledge and ability obtained through experience
– As you age, fluid intelligence decreases, while crystallized intelligence increases.
Gardner's theory of multiple intelligences
1.Linguistic: sensitivity to the subtle shades of the meanings of words
2. Musical: displayed by musicians and composers
3. Logical-mathematical: used in science and math
4. Spatial: ability to accurately perceive, manipulate and re-create forms
5. Bodily-kinesthetic: body control and skilled handling of objects
6. Interpersonal: skill in reading moods and intentions of others
7. Intrapersonal: ability to understand and react to one's own feelings
8. Naturalist: observe and interact with diverse species in nature
9. Spiritual: sense spiritual aspects of human experience and use them to adapt to the
environment
Which of these are closest to the things measured by
traditional intelligence tests?
•I suggest 1, 3 and some of 4.
Gardner's theory of multiple intelligences (cont.)
1.Linguistic: sensitivity to the subtle shades of the meanings of words
2. Musical: displayed by musicians and composers
3. Logical-mathematical: used in science and math
4. Spatial: ability to accurately perceive, manipulate and re-create forms
5. Bodily-kinesthetic: body control and skilled handling of objects
6. Interpersonal: skill in reading moods and intentions of others
7. Intrapersonal: ability to understand and react to one's own feelings
8. Naturalist: observe and interact with diverse species in nature
9. Spiritual: sense spiritual aspects of human experience and use them to adapt to the
environment
Are these all forms of intelligence?
•Many researchers might consider some of them (e.g., 2, 4, 5, 6, 7) to
be more accurately labeled as abilities rather than forms of intelligence.
Sternberg's Three facets of intelligence
• Proposes three kinds of intelligence: analytic, creative and
practical
• Analytic intelligence: more traditional type of intelligence
• Creative intelligence: ability to deal with novel tasks, and
to automatize them so difficult tasks become easy
– E.g., reading, arithmetic, driving a car
– Less intelligent people find these hard to make automatic
• Practical intelligence: ability to adapt to one's environment
– E.g., by changing jobs, schools, etc.
Traditional Intelligence Tests
• In the early 1900's, the French government wanted to know
which children would benefit from schooling and which
would not.
• Binet and Simon put together a series of tasks of increasing
difficulty, and tested children on each task. E.g.,
• Age 3:
1. Point to eyes, nose and mouth
2. Repeat three digits
3. Identify objects in a picture
• Age 7:
1. Show right hand and left ear
2. Describe a picture
3. Carry out three commands given simultaneously
Some examples of Binet and Simon’s tasks
(cont.)
•
Age 15:
1. Repeat 7 digits
2. Find three rhymes for a given word in 1 minute
3. Repeat a sentence of 26 syllables
•
•
They kept the tasks that they thought worked best, and
eventually had a test which assigned each child a "mental"
age.
If a 10-year-old scored at the mental age of 8.4, that child
was functioning intellectually at the 8-year-old level.
Stanford-Binet Scale
• Simon and Binet found the concept of mental age sufficient
for their purposes, but other researchers went further.
• Lewis Terman at Stanford University modified the BinetSimon scale for use in the U.S., and published it as the
Stanford-Binet Scale in 1916.
• Terman elaborated the concept of mental age further, and
used it to produce an intelligence quotient (=I.Q)
– Derived by dividing the child's mental age by her chronological
age and multiplying by 100
– IQ = (MA/CA) X 100
Stanford-Binet Scale (cont.)
• What would be the IQ in the above example (10 year old
child; MA of 8.4)?
•
Answer: IQ = (8.4/ 10 ) X 100 = IQ of 84
• Terman was particularly interested in highly intelligent
children, and used his test to identify a number with IQ's
over 140, whom he studied throughout their lives.
• They were more likely than others to do well at school, go
to college, publish writing, and they made more money.
• Also, contrary to the stereotype of the time (that smart
people were frail and unhealthy), they tended to be above
average in all indices of health and emotional adjustment
WAIS
• The Stanford-Binet has been revised several times, and is
still widely used.
• However the test most often used today for individual
intelligence assessments is what?
– The Wechsler Adult Intelligence Scale (current revision: the
WAIS-R).
• David Wechsler designed his test in the 1930's because at
that time the Stanford-Binet was for kids only, and
Wechsler wanted a test he could use with adults.
• There are eleven subtests of the WAIS-R, divided into two
categories: verbal subtests and performance subtests.
Verbal subtests
• Information
– How far is it from Montreal to Vancouver?
• Tests general knowledge
• Digit span
– Listen to the following list of numbers and repeat "2,7,9,4,8"
• Tests short-term memory
• Vocabulary
– What does the word overture mean?
• Tests vocabulary
• Arithmetic
– A shirt that actually sells for $30 is reduced in price by 15% during
a sale. What does the shirt cost during the sale?
• Tests quantitative ability
Verbal subtests (cont.)
• Comprehension
– Why do we have laws?
• Tests practical knowledge, social knowledge, and the ability to organize
information
• Similarities
– How are a pound and inch alike?
• Measures inductive reasoning ability
Performance subtests
• Picture Completion
– Looking at pictures of objects and seeing what parts are missing.
• Tests visual alertness and attention to detail
• Picture Arrangement
– Arrange sets of pictures in ways that tell a story.
• Tests sequencing ability and planning
• Block Design
– Arrange sets of blocks to match a pattern.
• Tests ability to analyze visual patterns
• Object Assembly
– Put parts of puzzle together to form an object?
• Tests ability to visualize final form from parts
Performance subtests (cont.)
• Digit Symbol
– Associate numbers with various symbols.
• Tests attentiveness, quickness and persistence in a simple perceptual-motor
task
WAIS-R Subtest Profile
IQ tests
• The WAIS does not use the IQ formula, (MA/CA) X 100,
so it is not technically an “IQ test.”
• Instead the WAIS uses a normal distribution scoring
scheme, which standardizes scores so that a person of
average intelligence would score 100, and 66% of all people
would score between 84 and 116.
• Standardized intelligence tests can be quite useful in
questions about a person's intellectual and cognitive
abilities, particularly in answering specific questions, but a
single IQ number tells us almost nothing about the profile of
a person’s intellectual abilities.
Normal Distribution of Intelligence Scores
IQ tests (cont.)
• A good thing about both the Stanford-Binet and the WAISR is that they are both reliable tests; this means that they
consistently produce the same score when given repeatedly
to the same person.
– The test-retest correlation for both is between 0.80 and 0.95;
quite high.
Problems with the IQ concept
• These intelligence tests are reliable, but are they valid?
• What does valid mean as applied to a psychological test?
– Answer: It means, do they really measure intelligence?
• I think they do measure fairly well a part of intelligence, but
they are too narrow; they miss the contextual and
experiential aspects of intelligence that other measures
catch.
– Will discuss later.
Problems with the IQ concept (cont.)
• What the Stanford-Binet and WAIS-R do well is predict
success in school
– people with high IQ's tend to do well in school; those with low IQs
tend to do poorly.
– However, there is an interesting developmental effect in this
correlation - see next figure.
IQ and Academic Achievement:
Correlations at Different Educational Levels
Why do you think the correlations get smaller as the educational level gets higher?
•Likely at least partly because of the restricted range of the students at the higher
levels:
•Almost all student going to graduate school have high levels of intelligence (I.e.
intelligence is more equal among students than in elementary school) so other
factors become more important in differentiating students and predicting student
success.
Problems with the IQ concept (cont.)
• A person's score on an intelligence test can be affected by a
number of things besides his 'real' intelligence, such as the
person's attitude toward the test, the skill of the test giver,
the student's prior test experience, whether the student is ill,
tired, etc.
• Standardized intelligence tests may show some cultural
bias.
– Many researchers claim that intelligence tests are biased
against minority groups (such as black Americans and
First Nations people) who do not have the middle class
background that critics claim the tests are designed for.
Time to try a few questions!
1. What number comes next in the following sequence:
1 2 5 6 9 10 ___
2. Filthy is to disease as clean is to __________
3. What number comes next in the sequence, one, two, three, __________?
4. As wallaby is to animal so cigarette is to __________
5. You are out in the bush with your wife and young children and you are all hungry. You have a rifle and bullets. You see
three animals all within range - a young emu, a large kangaroo and a small female wallaby. Which should you shoot for
food?
a. Young emu b. Large kangaroo c. Small female wallaby (circle your answer)
6. Many people say that "Juneteenth" (June 19) should be made a legal holiday because this was the day when:
(a) the slaves were freed in the USA, (b) the slaves were freed in Texas, (c) the slaves were freed in Jamaica, (d) the
slaves were freed in California, (e) Martin Luther King was born, (f) Booker T. Washington died.
7. If you throw the dice and 7 is showing on the top, what is facing down?
(a) 7, (b) snake eyes, (c) boxcars, (d) little Joes, (e) 11.
8. "Bird" or "Yardbird" was the "jacket" that jazz lovers from coast to coast hung on:
(a) Lester Young, (b) Peggy Lee, (c) Benny Goodman, (d) Charlie Parker, (e) "Birdman of Alcatraz."
9. Hattie Mae Johnson is on the County. She has four children and her husband is now in jail for non-support, as he was
unemployed and was not able to give her any money. Her welfare check is now $286 per month. Last night she went
out with the highest player in town. If she got pregnant, then nine months from now how much more will her welfare
check be?
(a) $80, (b) $2, (c) $35, (d) $150, (e) $100.
Answers
1.
Answer is 13. Add 1 to the first number, then add 3, then 1, then 3, etc
2. Health - If you believe that germs cause illness and if you believe that absence of "filth"
signifies the absence of germs.
3. One, two, three, many....the kuuk thaayorre system of counting only goes to three...thana,
kuthir, pinalam, mong, mong, mong, etc. The word mong is best translated as "many" since
it can mean any number between 4 and 9 or 10 after which yuur mong (many figures)
would be more appropriate.
4. The right answer is "tree". This stems from the kuuk thaayorre speakers early experience with
tobacco which was "stick" tobacco, hence it is classified with tree.
5. The small female wallaby is the right answer. Emu is a food that may be consumed only by
very old people. Kangaroos (especially large ones) may not be eaten by parents or their
children. The children will get sick otherwise. Everyone knows that....don't they?
6.
b) The slaves were freed in Texas
7.
a) 7
8.
d) Charlie Parker
9.
a) $80
•
Questions 1, 2 taken from standard American intelligence test; questions 3,4,5, taken from
“Original Australian Culture Test”, and relate to the culture of the Edward River
Community in Far North Queensland; questions 6-9 taken from Dove, A. The "Chitling"
Test. From Lewis R. Aiken, Jr. (1971). Psychological and educational testings. Boston:
Allyn and Bacon, and are based on 1970s black American culture.
Problems with the IQ concept (cont.)
• There are other problems in measuring and
assigning a single number to a trait as complex
as intelligence.
• As almost all researchers in the area
acknowledge, intelligence is a collection of
abilities, not a single, unitary “thing”.
Individual Differences in IQ:
Genes or Environment?
• The answer is: more genes than environment, but
environment is still important.
Contribution of twin and adoption studies
•
•
Twin studies have been very useful to psychologists in disentangling nature and
nurture.
Evidence regarding the importance of genes for determining IQ:
– The correlation between the IQ of identical twins reared together is about 0.85.
Remember, a correlation of 1.0 means complete similarity
Contribution of twin and adoption studies (cont.)
•
•
The correlation between the IQ of identical twins reared together is about 0.85.
Is that conclusive evidence that identical genes = almost identical IQ's?
– No, not necessarily, because identical twins reared together share the same
environment as well as identical genes.
Contribution of twin and adoption studies (cont.)
• And identical twins raised apart have IQ's that correlate at about .70.
• That figure therefore gives a good estimate of how much of our
intelligence was determined by our genes.
Contribution of twin and adoption studies (cont.)
• We now estimate that 50% to 70% of the variance in IQ comes from
genes, and about 30% to 40% from environmental sources.
• Although home and school environment do influence intelligence, the
genes you get from your parents will in most circumstances be the
most important factor
An analogy to running speed
• A person's running speed can be increased by training, but
the kind of body and physiology that they inherit from their
parents may be even more important in determining how
fast they run.
• However, almost everyone's running speed can be increased
past where it is now by training.
Reaction range and IQ
• Reaction range concept is very useful in understanding the
relative influence of genes and environmental factors on IQ.
Reaction range and IQ (cont.)
• Reaction range idea suggests that what we inherit is not a single
fixed level of overall intelligence but rather a range of intelligence,
with the lower and upper limits determined by the genes we inherit,
but with variation within those limits influenced by the environment.
Reaction range and IQ (cont.)
• One interesting aspect of this perspective is that some people may
inherit greater reaction ranges than others.
High IQs, genius and creativity (cont.)
• People with IQ's of 130 or more are considered gifted, and
the average university student has an IQ of about 115.
• There has been a lot of attention paid to people with 'genius'
IQ's.
– Sometimes defined as 1Qs > 140
– Do you think”genius should be defined by an IQ score?
• I think this is an inappropriate use of term "genius"; I prefer
to define a "genius" as someone who revolutionizes an
important area or discipline so that it is quite different as a
result of their contribution.
– E.g., Shakespeare, Mozart, Jefferson, Curie, Einstein, Picasso,
High IQs, genius and creativity (cont.)
• Some of these people probably didn't have an IQ of 140, but
their contributions fundamentally altered their fields.
• There are thousands of people with IQ's of 140 who making
no fundamental contribution to any field (just like the most
of us).
• They are not geniuses; they are people who score high on
IQ tests.