chapter 11 testing and individual differences. validity and reliability validity: a property...
TRANSCRIPT
Chapter 11
Testing and Individual Differences
Validity and Reliability Validity: A property exhibited by a test that
measures what it is supposed to measureFace validityContent validity
Item analysis
Criterion validity Reliability: A property exhibited by a test that
yields the same results over timeTest-retest reliabilityAlternate form reliabilitySplit-half reliability
Standardization and Norms
Scientists use statistics to establish a normal curve
This curve can be used to describe most phenomena (IQ for example)
Normal range: Scores falling near the middle of a normal distribution
The Normal Distribution of IQ Scores
Types of Tests Objective tests: can be scored easily by
machine Subjective tests: individuals are given an
ambiguous figure or an open-ended situation and asked to describe what they see or finish a story
Inter-rater reliability: measures how similarly two different test scorers would score a test
Intelligence: includes acquiring knowledge, ability to reason, solve problems
How is IntelligenceMeasured?
Intelligence testing has a history of controversy, but
most psychologists now view intelligence as a normally
distributed trait that can be measured by performance on
a variety of tasks
How is IntelligenceMeasured?
Binet-Simon Test – compared a child’s mental age to his or her chronological age Current performance, not measure of innate intelligence Identify those that need help, not to label Training & opportunity could affect intelligence Empirical – observed child’s performance
U.S. - widespread for the assessment of Army recruits, immigrants, and schoolchildren
The Stanford-Binet: standardized its administrations and its age-level norms; most respected
How is IntelligenceMeasured?
Intelligence quotient: Numerical score on an intelligence test, dividing mental age by chronological age and multiplying by 100 (IQ = MA/CA x 100)
Problems: Adults appeared to be mentally retarded!!! Original IQ has been abandoned in favor of a mental ability
score based on performance relative to the average performance of others the same age.
Achievement test – measures knowledge of a subject Aptitude test – measures capacity for learning Wechsler (AIS) and (ISC) – less on formal schooling
The Normal Distribution of IQ Scores
The Exceptional Child Mental retardation: Often conceived as
representing the lower 2% of the IQ rangeLower than IQ of 70“significant sub-average intellectual functioning”Limitations in at least 2 areas
CausesDown Syndrome – geneticFetal Alcohol Syndrome - environmentalPhenylketonuria (PKU) – caught earlydiet
The Exceptional Child
Giftedness: Often conceived as representing the upper 2% of the IQ rangeHigher than IQ of 130Terman (1921) - 1528 kids w/ IQ 135+
High correlation between IQ and academic performance
Healthy, happy, well-adjusted, successful
What Are the Componentsof Intelligence?
Some psychologists believe that the essence of
intelligence is a single, general factor, while others believe intelligence is best described as a collection of
distinct abilities
Psychometric Theories of Intelligence
Psychometrics: mental measurements g Factor: General ability as the main factor
underlying all intelligent mental activity (Spearman)
Crystallized intelligence: Knowledge a person has acquired, plus the ability to access that knowledge
Increases with age until around 75 (Cattell)
Fluid intelligence: The ability to see complex relationships and solve problems
Decreases slowly with age – esp 75+ (Cattell)
What Are the Components of Intelligence?
Evidence against the g factor… Savant syndrome: Found in individuals who
have a remarkable talent even though they are mentally slow in other domains
Kim Peek – Rain Man Stephen Wiltshire http://www.youtube.com/watch?v=a8YXZTlwTAU
Cognitive Theories of Intelligence
Beyond emphasis on vocab, logic, problem solving & other skills to predict school success.
Cognitive processes that contribute to success in many areas of life.Sternberg’s Triarchic TheoryGardner’s Multiple Intelligences
Sternberg’s Triarchic Theory
Practical Intelligence: ability to cope with the environment; aka street smarts
Analytical Intelligence: ability to analyze problems and find correct answers; ability measured by most IQ tests; aka logical reasoning
Creative Intelligence: form of intelligence that helps people see new relationships among concepts
Cognitive TheoriesGardner’s Multiple Intelligences
LinguisticLinguistic
Logical-MathematicalLogical-Mathematical
SpatialSpatial
MusicalMusical
Bodily-KinestheticBodily-Kinesthetic
InterpersonalInterpersonal
IntrapersonalIntrapersonal
Gardner’s Multiple IntelligencesLinguisticLinguistic
Logical-Mathematical
Spatial
Musical
Bodily-Kinesthetic
Interpersonal
Intrapersonal
Often measured on IQ tests with reading comprehension and vocabulary tests
Gardner’s Multiple IntelligencesLinguistic
Logical-MathematicalLogical-Mathematical
Spatial
Musical
Bodily-Kinesthetic
Interpersonal
Intrapersonal
Often measured on IQ tests with analogies, math problems and logic problems
Gardner’s Multiple IntelligencesLinguistic
Logical-Mathematical
SpatialSpatial
Musical
Bodily-Kinesthetic
Interpersonal
Intrapersonal
Ability to form mental images of objects and think about their relationships in space
Gardner’s Multiple IntelligencesLinguistic
Logical-Mathematical
Spatial
MusicalMusical
Bodily-Kinesthetic
Interpersonal
Intrapersonal
Ability to perceive and create patterns of rhythms and pitches
Gardner’s Multiple IntelligencesLinguistic
Logical-Mathematical
Spatial
Musical
Bodily-KinestheticBodily-Kinesthetic
Interpersonal
Intrapersonal
Ability for controlled movement and coordination
Gardner’s Multiple IntelligencesLinguistic
Logical-Mathematical
Spatial
Musical
Bodily-Kinesthetic
InterpersonalInterpersonal
Intrapersonal
Ability to understand other people’s emotions, motives and actions
Gardner’s Multiple IntelligencesLinguistic
Logical-Mathematical
Spatial
Musical
Bodily-Kinesthetic
Interpersonal
IntrapersonalIntrapersonal
Ability to know oneself and to develop a sense of identity
Gardner’s Three New Intelligences
Naturalistic intelligence Spiritual intelligence Existential intelligence
How Do Psychologists Explain IQ Differences
Among Groups?
While most psychologists agree that both heredity and
environment affect intelligence, they disagree on the source of IQ differences
among racial and social groups
How Do Psychologists Explain IQ Differences Among Groups? Hereditarian arguments maintain that
intelligence is substantially influenced by genetics
Environmental approaches argue that intelligence can be dramatically shaped by influences such asHealthEconomicsEducation
Heritability and Group Differences
Heritability: Amount of trait variation within a group, raised under the same conditions, that can be attributed to genetic differences
Heritability says nothing about between-group differences
Heritability and Group Differences
Research with twins and adopted children shows genetic influences on a wide range of attributes, including intelligence
Research has also shown that racial and class differences in IQ scores can be eliminated by environmental changes