PSYA02 CHAPTER 10 – INTELLIGENCE
- 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:
- Few things are more dangerous than a man with a mission.
- In the 1920s, psychologist Henry Goddard administered intelligence tests to arriving immigrants
at Ellis Island and concluded that the overwhelming majority of Jews, Hungarians, Italians, and
Russians were “feebleminded.”
- intelligence tests have occasionally been used to further detestable ends is especially ironic
because, as we are about to see, such tests were developed for the most noble of purposes: to
help underprivileged children succeed in school.
THE INTELLIGENCE QUOTIENT:
- So they set out to develop an objective test that would provide an unbiased measure of a child’s
- the tasks they tried included solving logic problems, remembering words, copying pictures,
distinguishing edible and inedible foods, making rhymes, and answering questions such as,
“When anyone has offended you and asks you to excuse him, what ought you to do?”
- Binet and Simon designed their test to measure a child’s aptitude for learning independent of
the child’s prior educational achievement, and it was in this sense that they called theirs a test of
- hey suggested that teachers could use their test to estimate a child’s “mental level” simply 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.
- For example, a child who was 10 years old but whose score was about the same as the score of
the average 8-year-old was considered to have the mental level of an 8-year-old and thus to
need remedial education.
- German psychologist William Stern (1914) suggested that this mental level could be thought of
as a child’s mental age and that the best way to determine whether a child was developing
normally was to examine the ratio of the child’s mental age to the child’s physical age.
- ratio IQ a statistic obtained by dividing a person’s mental age by the person’s physical age
and then multiplying the quotient by 100
- deviation IQ 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.
- The good thing about the deviation IQ is that a 30-year-old cannot become a genius simply by
- The bad thing about the deviation IQ is that it does not allow comparisons between people of
THE LOGIC OF INTELLIGENCE TESTING:
- Affability, motivation, intact hearing, doting parents—all of these seem likely to influence 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 such as getting good grades in
school, becoming a group leader, earning a large income, finding the best route to the gym, or
inventing a greaseless burrito
- would be highly impractical to actually measure these consequences, we instead devise an
easily administered set of tasks (e.g., a geometric puzzle) and questions whose successful
completion is known to be correlated with those consequences.
- intelligence tests do not “measure” intelligence in the same way that thermometers measure
- Rather, they measure the ability to answer questions and perform tasks that are highly
correlated with the ability to get good grades, solve real-world problems, and so on.
THE CONSEQUENCES OF INTELLIGENCE:
- intelligence test scores are highly correlated with just about every outcome that human beings
- Intelligence test scores predict a wide variety of other important consequences— from how
likely people are to commit crimes to how long people are likely to live
- Intelligence test scores also predict people’s performance on basic cognitive tasks.
- For instance, when people are briefly exposed to a pair of vertical lines and are asked to
determine which is longer, people with high intelligence test scores require less time to get the
- Interestingly, intelligence test scores also seem to be fairly good predictors of a person’s political
and religious attitudes:
- The more intelligent people are, the more likely they are to be liberal and atheistic
- intelligence tests scores are excellent predictors of a remarkable range of important
consequences. IQ clearly matters.
- Intelligence is a mental ability that enables people to direct their thinking, adapt to their
circumstances, and learn from their experiences.
- Intelligence tests measure responses that are known to be correlated with consequential
behaviors that are thought to be made possible by intelligence.
- Intelligence tests produce a score known as an intelligence quotient or IQ. Ratio IQ is the ratio of
a person’s mental to physical age and deviation IQ is the deviation of a person’s test score from
the average score of his or her peers.
- Intelligence test scores predict a person’s academic performance, job performance, health,
wealth, attitudes, and even basic cognitive abilities.
IS INTELLIGENCE ONE ABILITY OR MANY?:
- Michael Jordan’s brilliance on the basketball court and his mediocrity on the baseball field
proved beyond all doubt that these two sports require different abilities that are not necessarily
possessed by the same individual.
A HEIRARCHY OF ABILITIES: - factor analysis a statistical technique that explains a large number of correlations in terms of
a small number of underlying factors
- If there really is a single, general ability called intelligence that enables people to perform a
variety of intelligent behaviors, then those who have this ability should do well at just about
everything and those who lack it should do well at just about nothing.
- 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.
What did Spearmans research reveal?
- 1) it revealed that most of these measures were indeed positively correlated: Children who
scored high on one measure—for example, distinguishing the musical note C# from D—tended
to score high on the other measures—for example, solving algebraic equations.
- 2) although different measures were positively correlated, they were not perfectly correlated:
The child who had the very highest score on one measure didn’t necessarily have the very
highest score on every measure.
- Spearman combined these two facts into a two-factor theory of intelligence suggested
that every task requires a combination of a general ability (g) and skills that are specific to the
- 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
- Thurstone took this “clustering of correlations” to mean that there was actually 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 mental
- we have games called baseball and basketball but no game called athletics, so we have abilities
such as verbal ability and perceptual ability but no general ability called intelligence
- confirmatory factor analysis showed that the correlations between scores on different
mental ability tests are best described by a three-level hierarchy with a general factor (like
Spearman’s g) at the top, specific factors (like Spearman’s s) at the bottom, and a set of factors
called group factors (like Thurstone’s primary mental abilities) in the middle
- This hierarchy suggests that 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.
- Most intelligence test data are best described by a three-level hierarchy with general
intelligence (g) at the top, specific abilities (s) at the bottom, and a small number of middle-level
abilities (m) (sometimes called group factors) in the middle.
THE MIDDLE LEVEL ABILITIES:
- Most psychologists agree that there are very specific mental abilities as well as a very general
mental ability and that one of the important challenges is to describe the middle-level abilities
that lie between them. - Some psychologists have taken a data-based approach to this problem by starting with people’s
responses on intelligence tests and then looking to see what kinds of independent clusters these
- Other psychologists have taken a theory-based approach to this problem by starting with a
broad survey of human abilities and then looking to see which of these abilities intelligence tests
measure—or fail to measure.
THE DATA BASED APPROACH:
- One way to determine the nature of the middle-level abilities is to start with the data and go
where they lead us.
- imagine that we tested how quickly and well a large group of people could (a) balance teacups,
(b) understand Shakespeare, (c) swat flies, and (d) sum the whole numbers between one and a
- Now imagine that we computed the correlation between scores on each of these tests and
observed a pattern of correlations
- This pattern suggests that a person who can swat flies well can also balance teacups well and
that a person who can understand Shakespeare well can also sum numbers well, but that a
person who can swat flies well and balance teacups well may or may not be able to sum
numbers or understand Shakespeare well.
- From this pattern, we could conclude that there are two middle-level abilities, which we might
call “physical coordination” (the ability that allows people to swat flies and balance teacups
well) and “academic skill” (the ability that allows people to understand Shakespeare and sum
- simply by examining the pattern of correlations between different tests, we can divine the
nature and number of the middle-level abilities.
- Carroll found that the pattern of correlations among these tests suggested the existence of eight
independent middle-level abilities:
o memory and learning,
o visual perception, o auditory perception,
o retrieval ability,
o cognitive speediness,
o processing speed,
o crystallized intelligence
o fluid intelligence.
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.
- its conclusions are based on hard evidence.
- it is incapable of discovering any middle-level ability that intelligence tests didn’t already
- Psychologist Robert Sternberg suggests that there are three kinds of intelligence, which he
calls analytic intelligence, creative intelligence, and practical intelligence.
- Analytic intelligence is the ability to identify and define problems and to find strategies for
- creative intelligence is the ability to generate solutions that other people do not;
- practical intelligence is the ability to apply and implement these solutions in everyday
- Psychologist Howard Gardner also believes that standard intelligence tests