Chapter 10- Intelligence
-Williams Syndrome caused by absence of 20 genes in chromosome 7. Impairs a person’s general cognitive abilities and yet
leaves them with a talent for music and language.
-Intelligence is the ability to direct one’s thinking, adapt to one’s circumstances, and learn from one’s experiences
How Can Intelligence be Measured?
-Henry Goddard administered intelligence tests to arriving immigrants at Ellis Island and concluded the majority of Jews,
Hungarians, Italians and Russians were “feebleminded”. Also used his tests to identify feebleminded American families
(largely responsible for the nation’s social problems), suggest the government should segregate them in isolated colonies and
take away the power of procreation.
- Intelligence tests were first developed to help underprivileged children succeed in school
The Intelligence Quotient
-The French government called on psychologist Alfred Binet and physician Theodore Simon to develop a test that would allow
educators to develop remedial programs for the children who lagged behind. They set out to develop an objective test that
would provide an unbiased measure of a child’s ability (unbias based on the child’s social status)
-They looked for tasks that could distinguish the best and worst students and thus predict a future child’s success in school.
This included solving logic problems, remembering words, copying pictures, distinguishing edible from non edible foods,
making rhymes and answering questions about social situations. They settled on 30 tasks said to measure a child’s “natural
-Binet and Simon designed their test to measure a child’s aptitude for learning independent of the child’s prior educational
achievement (nat. Intelligence).
-Tests could be used to estimate a child’s “mental level” by computing the average test score of children in different age
groups and then finding the age group whose average test score was most like that of the child’s.
-William Stern (1914) suggested that this mental level could be thought of as a child’s mental age
-Lewis Terman (1916) formalized this comparison with the intelligence quotient or ratio IQ which is a statistic obtained by
dividing a person’s mental age by the person’s physical age and then multiplying the quotient by 100.
-As a result of anomalies, researchers devised a new measure called the deviation IQ, which is a statistic obtained by dividing
a person’s test score by the average test score of people in the same age group and then multiplying the quotient by 100. Bad
thing about this is that it does not allow comparisons between people at different ages.
The Logic of Intelligence Testing
- Affibility, motivation, intact hearing, doting parents, are all likely influences of a child’s scholastic performance.
-To design an intelligence test we begin with the assumption that a property called intelligence leads people to experience a
wide variety of consequences. But it was highly impractical to actually measure these consequences, they instead devised an
easily administered set of tasks (geometric puzzle), whose successful completion is known to be correlated with those
consequences The Consequences of Intelligence
-an intelligence test is a measurement of a person’s performance on tasks that are correlated with the consequences
that intelligence produces. They do not measure intelligence per say, but the ability to answer questions and perform
tasks that are highly correlated with the ability to get good grades, solve real world problems... etc.
-Most widely known intelligence test, Stanford-Binet (based on binet and simon’s original test but has been modified,
especially by Lewis Terman) and the WAIS (the Wechsler Adult Intelligence Scale). WAIS’s 13 subtests involve seeing
similarities and differences, drawing inferences, remembering... etc. Only 3 of 13 require anything written down and none
require writing words
-Intelligence test score is the best predictor of the number of years of education an individual will receive. It also predicts a
person’s occupational status and income. Job performance correlates more highly with intelligence than with factors such as
performance during a job interview or education. Predict people’s performance on basic cognitive tasks. Fairly good
predictors of political and religious attitudes, more intelligent are more likely to be liberal and atheist. They predict a lot of
other consequences from how likely people are to commit crimes to how long people are likely to live.
A Hierarchy of Abilities
-Charles Spearman was a student of Wilhelm Wundt . He invented a technique known as factor analysis which is a statistical
technique that explains a large number of correlations in terms of a small number of underlying factors.
-If intelligence is a single general ability, then there should be a very strong positive correlation between people’s
performances on all kinds of tests. Spearman wanted to find this out by measuring how well school aged kids could
discriminate small differences in color, auditory pitch and weight and he then correlated these scores with the children’s
grades in different academic subjects as well as with their teacher’s estimates of their intellectual ability. It revealed that
most of their measures were positively correlated: the most replicated result in all of psychology.
-Spearman’s research revealed that although different measure were positively correlated, they who had they very highest
score on one measure didn’t necessarily have the very highest score on every measure. He combined these two facts into a
two factor theory of intelligence which suggested that every task requires a combination of a general ability (g) and skills that
are specific to the task (s).
-Louis Thurstone noticed that while scores on most tests were indeed positively correlated, scores on one kind of verbal test
were more highly correlated with scores on another kind of verbal test than they were with scores on perceptual tests. Took
this clustering of correlations to mean that there was no such thing as g and that there were instead a few stable and
independent mental abilities such as perceptual ability, verbal ability, and numerical ability which he called the primary
-we have abilities such as verbal and perceptual abilities but not general ability called intelligence
-a new mathematical technique called confirmatory factor analysis brought the debate to a quiet close by revealing that
Spearman and Thurstone had each been right.
-Correlations between scores on different mental ability tests are best described by a three level hierarchy: general factor
(like Spearman’s) at the top, specific factors (spearman) at the bottom and a set of factors called group factors (Thurstone’s
primary mental abilities) in the middle.
-People have a very general ability called intelligence which is made up of a small set of middle level abilities, which are made
up of a large set of specific abilities that are unique to particular tasks. The Data Based Approach
-one way to determine the nature of the middle level abilities is to start with that data and go where they lead us. We could
compute the correlations between the performances of a large number of people on a large number of tests and then see
how those correlations cluster.
-John Carroll found that the pattern of correlations among these tests suggested the existence of eight independent middle
level abilities: memory and learning, visual perception, auditory perception, retrieval ability, cognitive speediness, processing
speed, crystallized intelligence, and fluid intelligence.
-Fluid intelligence is the ability to see abstract relationships and draw logical inferences and crystallized intelligence is the
ability to retain and use knowledge that was acquired through experience. If we think of the brain as information processing
devic e:crystallized intelligence is the information part and fluid intelligence is the processing part.
-Crystallized intelligence is generally assessed by tests of vocabulary, factual information, and so on, fluid intelligence is
generally assessed by tests that pose novel, abstract problems that must be solved under time pressure, such as Raven’s
Progressive Matrices Test
The Theory Based Approach
-The data based approach attempts to discover the middle level abilities by analyzing people’s responses to questions on
intelligence tests. Good thing: conclusions based on hard evidence. Bad thing: it is incapable of discovering any middle level
ability that intelligence tests didn’t already measure. Scores from these tests may be incapable of revealing the middle level
abilities such as imagination or creativity.
-Robert Sternberg suggests three kinds of intelligences: analytic intelligence, creative intelligence and practical intelligence.
Analytic intelligence is the ability to identify and define problems and to find strategies for solving them; creative intelligence
is the ability to generate solutions that other people do not; and practical intelligence is the ability to apply and implement
these solutions in everyday settings.
-Sternberg said standard intelligence tests confront people with clearly defined problems that have one right answer and
then supply all information needed to solve them= analytic intelligence. Everyday life confronts people with situations in
which they must formulate the problem, find the information needed to solve it, and then choose among multiple acceptable
solutions= practical intelligence.
-tests of practical intelligence are better than tests of analytical intelligence at predicting a person’s job performance.
- Prodigies- people of normal intelligence who have an extraordinary ability. Savants- people of low intelligence who have an
-Howard Gardner’s observations of people with and without brain damage led him to conclude of eight distinct kinds of
intelligence: linguistic, logical –mathematical, spatial, musical, bodily-kinesthetic, interpersonal, intrapersonal, and
naturalistic. He says standard intelligence tests only measure the first three because they are most valued by western culture.
-some researchers believe that different cultures have different conceptualizations of intelligence. They argue that every
culture values the ability to solve important problems and that why really distinguishes cultures is the kinds