Copyright © Allyn & Bacon 2007 Chapter 11 Testing and Individual Differences

Copyright © Allyn & Bacon 2007 Measuring individual differences is an essential component of psychology, but strict guidelines and ethical standards must be followed to ensure results and conclusions are valid and appropriate. How Do We Measure Individual Differences?

Copyright © Allyn & Bacon 2007 Validity and Reliability Validity – A property exhibited by a test that measures what it purports to measure. Face validity Content validity Criterion validity

Copyright © Allyn & Bacon 2007 Validity Face validity Measures whether a test looks like it tests what it is supposed to test. Content validity Each item is representative of the larger body of knowledge about the subject that the test covers. Criterion validity Accurately measures performance of the test taker against a specific learning goal.

Copyright © Allyn & Bacon 2007 Validity and Reliability Reliability – A property exhibited by a test that yields the same results over time. Test-retest reliability Split-half reliability Inter-rater reliability

Copyright © Allyn & Bacon 2007 Reliability Test-retest reliability People get about the same scores when they take the test more than once. Split-half reliability A test is split into 2 parts and an individual’s scores on both halves are compared. Inter-rater reliability A measure of how similarly two different test scorers would score a test.

Copyright © Allyn & Bacon 2007 Standardization and Norms Normal range Scores falling near the middle of a normal distribution.

Copyright © Allyn & Bacon 2007 The Normal Distribution of IQ Scores Few Many Number of Persons IQ Normal Range

Copyright © Allyn & Bacon 2007 Types of Tests Objective tests can be scored easily by machine. In subjective tests, individuals are given an ambiguous figure or an open-ended situation and asked to describe what they see or finish a story.

Copyright © Allyn & Bacon 2007 Ethics and Standards in Testing Ethical concerns related to testing involve: The confidentiality of the test results How to report the results How to use the test to compare individuals

Copyright © Allyn & Bacon 2007 How is Intelligence Measured? 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.

Copyright © Allyn & Bacon 2007 How is Intelligence Measured? Intelligence quotient (IQ) – A numerical score on an intelligence test, originally computed by dividing a person’s mental age by chronological age and multiplying by 100.

Copyright © Allyn & Bacon 2007 How to Calculate IQ IQ = x 100 Chronological Age Mental Age

Copyright © Allyn & Bacon 2007 How is Intelligence Measured? Binet-Simon Test calculated a child’s mental age and compared it to his or her chronological age. In America, testing became widespread for the assessment of Army recruits, immigrants, and school children. The Stanford-Binet Intelligence Scale is the most respected of the new American tests of intelligence.

Copyright © Allyn & Bacon 2007 How is Intelligence Measured? Wechsler tests Measure a variety of different skills (vocab, verbal comprehension, arithmetic ability, similarities, block design, etc.) WAIS – Wechsler Adult Intelligence Scale WISC – Wechsler Intelligence Scale for Children WPPSI – Wechsler Preschool and Primary Scale of Intelligence

Copyright © Allyn & Bacon 2007 What Are the Components of 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.

Copyright © Allyn & Bacon 2007 Theories of Intelligence Charles Spearman g Factor A general ability, proposed by Spearman as the main factor underlying all intelligent mental activity.

Copyright © Allyn & Bacon 2007 Theories of Intelligence Raymond Cattell Crystallized intelligence – The knowledge a person has acquired, plus the ability to access that knowledge. Fluid intelligence – The ability to see complex relationships and solve problems.

Copyright © Allyn & Bacon 2007 Robert Sternberg’s Triarchic Theory Practical Intelligence Analytical Intelligence Creative Intelligence

Copyright © Allyn & Bacon 2007 Sternberg’s Triarchic Theory Ability to cope with the environment; “street smarts” Practical Intelligence Analytical Intelligence Creative Intelligence

Copyright © Allyn & Bacon 2007 Sternberg’s Triarchic Theory Ability to analyze problems and find correct answers; ability measured by most IQ tests also called logical reasoning Practical Intelligence Analytical Intelligence Creative Intelligence

Copyright © Allyn & Bacon 2007 Sternberg’s Triarchic Theory Form of intelligence that helps people see new relationships among concepts; involves insight and creativity Practical Intelligence Analytical Intelligence Creative Intelligence

Copyright © Allyn & Bacon 2007 Howard Gardner’s Multiple Intelligences Linguistic Logical-Mathematical Spatial Musical Bodily-Kinesthetic Interpersonal Intrapersonal

Copyright © Allyn & Bacon 2007 Gardner’s Multiple Intelligences Linguistic Logical-Mathematical Spatial Musical Bodily-Kinesthetic Interpersonal Intrapersonal Often measured on IQ tests with reading comprehension and vocabulary tests

Copyright © Allyn & Bacon 2007 Gardner’s Multiple Intelligences Linguistic Logical-Mathematical Spatial Musical Bodily-Kinesthetic Interpersonal Intrapersonal Often measured on IQ tests with analogies, math problems and logic problems

Copyright © Allyn & Bacon 2007 Gardner’s Multiple Intelligences Linguistic Logical-Mathematical Spatial Musical Bodily-Kinesthetic Interpersonal Intrapersonal Ability to form mental images of objects and think about their relationships in space

Copyright © Allyn & Bacon 2007 Gardner’s Multiple Intelligences Linguistic Logical-Mathematical Spatial Musical Bodily-Kinesthetic Interpersonal Intrapersonal Ability to perceive and create patterns of rhythms and pitches

Copyright © Allyn & Bacon 2007 Gardner’s Multiple Intelligences Linguistic Logical-Mathematical Spatial Musical Bodily-Kinesthetic Interpersonal Intrapersonal Ability for controlled movement and coordination

Copyright © Allyn & Bacon 2007 Gardner’s Multiple Intelligences Linguistic Logical-Mathematical Spatial Musical Bodily-Kinesthetic Interpersonal Intrapersonal Ability to understand other people’s emotions, motives and actions

Copyright © Allyn & Bacon 2007 Gardner’s Multiple Intelligences Linguistic Logical-Mathematical Spatial Musical Bodily-Kinesthetic Interpersonal Intrapersonal Ability to know oneself and to develop a sense of identity

Copyright © Allyn & Bacon 2007 Gardner’s Three New Intelligences Naturalistic intelligence - Allows people to classify things as members of diverse groups. Spiritual intelligence - The ability to think in abstract spiritual terms and to put oneself in a spiritual frame of mind. Existential intelligence - Permits individuals to think about the purpose of existence and the meaning of things like death and love.

Copyright © Allyn & Bacon 2007 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.

Copyright © Allyn & Bacon 2007 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 as: Health Economics Education

Copyright © Allyn & Bacon 2007 Heritability and Group Differences Heritability – Amount of trait variation within a group, raised under the same conditions, that can be attributed to genetic differences.

Copyright © Allyn & Bacon 2007 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.

Copyright © Allyn & Bacon 2007 End of Chapter 11