Chapter 11 Testing and Individual Differences Nothing bout

Chapter 11 Testing and Individual Differences Nothing ‘bout me! - Sting

Epilogue (Nothing ‘bout me) - Sting Lay my head on the surgeon's table Take my fingerprints if you are able Pick my brains pick my pockets Steal my eyeballs and come back for the sockets Run every kind of test from A to Z And you'll still know nothing 'bout me Run my name though your computer Mention me in passing to your college tutor Check my records check my facts Check if I paid my income tax Pore over everything in my C. V. But you'll still know nothing 'bout me You don't need to read no books on my history I'm a simple man, it's no big mystery In the cold weather, a hand needs a glove At times like this, a lonely man like me needs love Search my house with a fine tooth comb Turn over everything 'cause I won't be at home Set up your microscope and tell me what you see You'll still know nothing 'bout me

How Do We Measure Individual Differences? 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

Test Validity - A property exhibited by a test that measures what it proposes to measure Face Validity – Looks like it tests what it’s supposed to or claims to test Content Validity – Contains a representation of the larger body of knowledge

Test Validity - A property exhibited by a test that measures what it proposes to measure Item Analysis – Each question on the test is checked to make sure it matches the test objectives Criterion Validity – The test is measured against an overall goal or proficiency (meeting the criteria).

Test Reliability - A property exhibited by a test that yields the same results over time Test-Retest Reliability – If you take a test again, you should get the same or similar results. Split-Half Reliability – The test is split into two equal parts (oddeven) and scores are compared. Copyright © Allyn & Bacon 2007

Test Reliability - A property exhibited by a test that yields the same results over time Inter-rater reliability A method of reliability to ensure how similarly two different test scorers would score a test

Standardization and Norms (See Chapter 2 notes for review!) Standardized Tests and Norms Scientists use statistics to establish a normal curve 1. Administration and scoring guidelines are the same for each person who takes the test (e. g. SAT’s, CAHSEE) This curve can be used to describe most phenomena Normal range – Scores falling near the middle of a normal distribution 2. Results are used to draw inferences from.

The Exceptional Child Average Range – Often conceived as representing the portion within 1 SD above and below the mean (68% of the scores). Mental retardation/ Cognitively Deficient – Often conceived as representing the lower 2% of the IQ range Above Average and Below Average – Often conceived as representing the portion within 2 SD above or below the mean (the 14% on either side). Giftedness – Often conceived as representing the upper 2% of the IQ range

Normal Distribution Mean 68% of values 95% of values 99% of values % of scores Standard Deviations from the Mean Percentiles Z Scores 2% -4 -3 0 -4 -3 60 70 14% -2 2 nd -2 80 34% -1 16 th -1 90 34% 0 50 th 0 100 14% 2% +1 84 th +2 +1 +2 +3 +4 110 120 130 140 98 th +3 100 th +4

Wechsler Intelligence Test

Types of Tests Objective tests

Types of Tests Subjective tests

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 The impact of tests on society as a whole

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

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 schoolchildren The Stanford-Binet Intelligence Scale is the most respected of the new American tests of intelligence

How is Intelligence Measured? Intelligence quotient – Mental Age is the score the person receives on the test to show what they are cognitively able to do. Chronological Age is the age of the person at the time of testing. The original IQ calculation was abandoned in favor of standard scores based on the normal distribution

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

What Are the Components of Intelligence? Savant Syndrome – Copyright © Allyn & Bacon

Psychometric Theories of Intelligence g Factor – A general ability, proposed by Spearman as the main factor underlying all intelligent mental activity

Psychometric Theories of Intelligence Crystallized intelligence – Fluid intelligence –

Cognitive Theories of Intelligence Sternberg’s Triarchic Theory Gardner’s Multiple Intelligences Copyright © Allyn &

Sternberg’s Triarchic Theory Practical Intelligence Analytical Intelligence Creative Intelligence

Gardner’s Three New Intelligences Naturalistic intelligence Spiritual intelligence Existential intelligence

Cultural Definitions of Intelligence Cross-cultural psychologists have shown that “intelligence” has different meanings in different cultures

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

Heritability and Group Differences Heritability – Heritability says nothing about betweengroup differences

Imagine that seeds from the same mixture are sown in normal and deficient soil. Although height differences within each box will be genetic (high heritability), the height difference between groups will be environmental, and heritability will be lower, because we will never know what the potential for their height could have been.

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

End of Chapter 11