Intelligence: the ability to acquire knowledge, to think and reason effectively, and to deal
adaptively with the environment.
Intelligence in Historical Perspective
Sir Francis Galton: Quantifying Mental Ability
• Eminence and genius seemed to occur within certain families
Alfred Binet’s Mental Tests
Modern intelligent-testing movement (20 century)
Binet’s 2 assumptions:
1. Mental abilities develop with age
2. The rate at which people gain mental competence is a characteristic of the person and is
fairly constant over time.
Mental age: the mental level or age at which a child is performing as determined by
“standardized interview” in which the child responds to a series of questions.
William Stern’s Intelligence quotient (IQ): the ratio of mental age to chronological age,
multiplied by 100: IQ=(mental age/chronological age) x 100.
Binet’s Legacy: An Intelligence-Testting Industry Emerges
Stanford-Binet (mid 1920’s): became widely accepted in North America as the gold standard for
measuring mental amplitude.
• Mostly verbal items
• Yielded a single IQ score
Army Alpha: a verbally oriented test that was used to screen large numbers of U.S. Army
recruits for intellectual fitness.
Army Beta: a non-verbal instrument using mazes, picture-completion problems, and digit-
Wechsler: believed intelligence should be measured as a group of distinct but related verbal and
Wechsler Adult Intelligence Scale (WAIS)
Wechsler Intelligence Scale for Children (WISC)
Weschler Preschool and Primary Scale of Intelligence (WPPSI)
The Nature of Intelligence
Approaches in the study of intelligence:
1. Psychometric approach: attempts to map the structure of intellect and to discover the
kinds of mental competencies that underlie test performance. 2. Cognitive processes approach: studies the specific thought processes that underlie those
The Psychometric Approach: The Structure of Intellect
Psychometrics: the statistical study of psychological tests.
• Tries to identify and measure differences in performance/provide a measurement-based
map of the mind.
Factor analysis: statistical technique that reduces a large number of measures to a smaller
number of clusters, or factors, with each cluster containing variables that correlate highly with
one another but less highly with variables in other clusters.
The g Factor: Intelligence as General Mental Capacity
g factor: intellectual performance is determined partly by a g factor, or general intelligence, and
partly by whatever special abilities might be required to perform that particular task. The g factor
cuts across all tasks, it constitutes the core of intelligence.
Intelligence as Specific Mental Abilities
Primary mental abilities (seven distinct abilities that human mental performance depend on):
1. Spatial ability
2. Perceptual speed
3. Numerical ability
4. Verbal meaning
6. Verbal fluency
7. Inductive reasoning
Crystallized and Fluid Intelligence
Crystallized intelligence (gc): the ability to apply previously acquired knowledge to current
• Vocabulary and information tests
• Basis for expertise
• Depends on the ability to retrieve previously learned information and problem-solving
schemas from long-term memory (previous learning and practice)
• As we age, we become more dependent on crystallized intelligence
Fluid intelligence (gf: the ability to deal with novel problem-solving situations for which
personal experience does not provide a solution.
• Inductive reasoning and problem solving
• Dependent primarily on the efficient functioning of the central nervous system rather than
on prior experience and cultural context.
• Requires the ability to reason abstractly, think logically, and manage information in
working (short-term) memory
• In early life, we use fluid memory Carroll’s Three-Stratum Model: A Modern Synthesis
Three-stratum theory of cognitive abilities: establishes three levels of mental skills-general,
broad, and narrow, arranged in a hierarchical model.
Cognitive Process Approaches: The Nature of Intelligent Thinking
Cognitive process theories: explore specific information-processing and cognitive processes
that underlie intellectual ability (why do people vary in mental skills?
Triarchic theory of intelligence: addresses both the psychological processes involved in
intelligent behaviour and the diverse forms that intelligence can take.
Three components of triarchic intelligence:
1. Metacomponents: the higher-order processes used to plan and regulate task performance
2. Performance components: the actual mental processes used to perform the task (i.e.
perceptual processing, retrieving appropriate memories and schemas from long-term
memory, and generating responses).
3. Knowledge-acquisition components: allows us to learn from our experiences, store
information in memory, and combine new insights with previously acquired information.
Stenberg’s belief of 3 different forms of intelligence:
1. Analytical intelligence involves the kinds of academically oriented problem-solving
skills measured by traditional intelligence tests.
2. Practical intelligence refers to the skills needed to cope with everyday demands and to
manage oneself and other people effectively. 3. Creative intelligence comprises the mental skills need to deal adaptively with novel
Broader Conception of Intelligence: Beyond Mental Competencies
Gardner’s theory of multiple intelligences: he currently defines eight (8) distinct varieties of
adaptive abilities, and a possible ninth variety.
1. Linguistic intelligence: the ability to use language well, as writers do
2. Logical-mathematical intelligence: the ability to reason mathematically and logically
3. Visuospatial intelligence: the ability to solve spatial problems or to succeed in a field
such as architecture
4. Musical intelligence: the ability to perceive pitch and rhythm and to understand and
5. Bodily-kinesthetic intelligence: the ability to control body movements and skillfully
manipulate objects, as demonstrated by a highly skilled dancer, athlete, or surgeon
6. Interpersonal intelligence: the ability to understand and relate well to others
7. Intrapersonal intelligence: the ability to understand oneself
8. Naturalistic intelligence: the ability to detect and understand phenomena in the natural
world, as a zoologist or meteorologist might
9. Existential intelligence (possible ninth intelligence): a philosophically oriented ability to
ponder questions about the meaning of one’s existence, life, and death.
Emotional intelligence: involves the abilities to read others’ emotions accurately, to respond to
them appropriately, to motivate oneself, to be aware of one’s own emotions, and to regulate and
control one’s own emotional responses.
Four (4) components of emotional intelligence:
1. Perceiving emotions: people’s accuracy in judging emotional expressions in facial
photographs, as well as the emotional tones conveyed by different landscapes and
2. Using emotions to facilitate thought: people’s ability to identify the emotions that
would best enhance a particular type of thinking.
3. Understanding emotions: people’s ability to specify the conditions under which their
emotions change in intensity or type, and one’s understanding of basic emotions that
blend together to create subtle emotions.
4. Managing emotions: people’s ability to indicate how they can change their own or
others’ emotions to facilitate success or increase interpersonal harmony.
*The Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) includes specific tasks to
measure each branch.
The Measurement of Intelligence
Increasing the Informational Yield From Intelligence Tests
Stanford-Binet now tests a wider range of abilities, such as:
• Verbal reasoning
• Abstract/visual reasoning
• Quantitive reasoning
• Short-term memory Should We Test For Aptitude Or Achievement?
Achievement test: designed to find out how much they have learned so far in their lives.
Aptitude test: containing novel puzzlelike problems that presumably go beyond prior learning
and are thought to measure the applicant’s potential for future learning and performance.
Psychometric Standards For Intelligence Tests
Psychological test: a method for measuring individual differences related to some psychological
concept, or construct, based on a sample of relevant behaviour in a scientifically designed and
controlled situation (construct=intelligence, scores=operational definition).
To the requirements of collecting a sample of relevant behaviour under standardized conditions,
attempting to control for other factors that could influence responses to the items, we must
examine three key components:
1. Reliability: refers to consistency of measurenment
• Test-retest reliability: assessed by administering the measure to the same group
of participants on two (or more) separate occasions and correlating the two (or
more) sets of scores.
• Internal consistency: consistency of measurement within the test itself.
• Interjudge reliability: consistency of measurement when different people
observe the same event or score the same test.
2. Validity: refers to how well a test actually measures what it is designed to measure.
• Construct validity: exists when a test successfully measures the psychological
construct it is designed to measure, as indicated by relations between test scores
and other behaviours that it should be related to.
• Content validity: refers to whether the items on a test measure all the knowledge
or skills that are assumed to underlie the construct of interest.
• Criterion-related validity: refers to the ability of test scores to correlate with
meaningful criterion measures.
3. Standardization: had two meaning: (1) the development of norms and (2) rigorously
controlled testing procedures.
• Norms: test scores derived from a large sample that represents part