Chapter 9: Intelligence and Psychological Testing

Vocabulary Achievement test Aptitude test Construct validity Content validity Convergent thinking Correlation coefficient Creativity Crystallized intelligence Criterion-related validity Deviation IQ scores Divergent thinking Emotional intelligence Fluid intelligence Heritability ratio Intelligence quotient IQ Intelligence test Mental age Mental retardation Normal distribution Percentile score Personality test Psychological test Reaction range Reification Reliability Split half reliability Standardization Standard Deviation Test norms Validity

Categorize all the terms to make sure you understand them Intelligence and Testing Tests personality achievement aptitude psychological intelligence Measures scoring validity content construct criterion reliability

VIP’s (prioritize) Alfred Binet David Wechsler Lewis Terman Howard Gardner Arthur Jensen Galton Scarr Steele Sternberg Winner

Psychological tests are standardized measures of behavior Mental ability tests Intelligence – general Aptitude – specific Personality scales Measure motives, interests, values, and attitudes

Mental ability tests intelligence tests are designed to measure general mental ability aptitude tests measure more specific mental abilities.

Personality measures there are no right or wrong answers, so they are referred to as scales measure a variety of motives, interests, values, and attitudes.

Key Concepts in Psychological Testing Standardization Reliability Validity

Standardization uniform procedures used in the administration and scoring of a test Test norms: where a score on a psychological test ranks in relation to other scores on that test…allows a psychologist to determine how a person scores relative to other people. Standardization group: sample of people that the norms are based on.

Reliability Consistency - repeated measurements should yield reasonably similar results Reliability estimates: based on the correlation coefficient Two sets of scores from two administrations of the same test are correlated; the closer the correlation comes to +1.00, the more reliable the test.

Validity ability of a test to measure what it was designed to measure Content validity: the degree to which the content of a test is representative of the domain it is supposed to cover physics questions on a psychology test would be poor content validity

Criterion-related validity: estimated by correlating subjects’ scores on a test with their scores on an independent criterion predictive ability Construct validity the extent to which there is evidence that a test measures a particular hypothetical construct are we really measuring intelligence with an IQ test? Construct validity is

Figure 9.2 Test-retest reliability

Figure 9.3 Correlation and reliability

Figure 9.4 Criterion-related validity

Figure 9.5 Construct validity

The validity of a personality test is best indicated by which of the following? The correlation between test scores and some other relevant measure The correlation between test scores and IQ The inverse correlation of the variables being tested The number of people in the test’s norming population The number of questions in the test that can be objectively scored

The validity of a personality test is best indicated by which of the following? The correlation between test scores and some other relevant measure The correlation between test scores and IQ The inverse correlation of the variables being tested The number of people in the test’s norming population The number of questions in the test that can be objectively scored

The Evolution of Intelligence Testing Sir Francis Galton (1869) Alfred Binet and Theodore Simon (1905) Lewis Terman (1916) David Wechsler (1955)

The Evolution of Intelligence Testing Sir Francis Galton (1869) Hereditary Genius Success runs in families because intelligence is inherited Test based on sensory acuity

The Evolution of Intelligence Testing Alfred Binet and Theodore Simon (1905) first intelligence test was designed to single out youngsters in need of special training expressed a child’s score in terms of mental age a 4 year-old who performed like the average 6 year-old had a mental age of 6 Binet-Simon Intelligence Scale

 In 1913 the United States Public Health Service administered a version of the newly invented Binet IQ test to immigrants arriving at Ellis Island. Professional researchers recorded that "79% of the Italians, 80% of the Hungarians, 83% of the Jews, and 87% of the Russians are feebleminded." Rather than challenging the validity of the test, the results served to reinforce negative images of immigrants.

The Evolution of Intelligence Testing Lewis Terman (Stanford, 1916) Stanford-Binet Intelligence Scale – a test revised for use in U.S. New scoring scheme Intelligence Quotient (IQ) dividing a child’s mental age by chronological age and multiplying by 10o made it possible to compare children of different ages.

The Evolution of Intelligence Testing David Wechsler (1955) Measured intelligence in adults Scales give more emphasis to nonverbal reasoning Verbal IQ Performance IQ Full scale IQ New scoring system based on normal distribution – deviation IQ

Alfred Binet’s most important contribution to psychology was in the area of Intelligence testing Visual perception Psychopathology Comparative psychology Classical conditioning

Alfred Binet’s most important contribution to psychology was in the area of Intelligence testing Visual perception Psychopathology Comparative psychology Classical conditioning

Figure 9.7 The normal distribution

Reliability and Validity of IQ tests Exceptionally reliable – reliability coefficients [correlation] into the .90’s Although they are intended to measure potential, IQ tests inevitably assess both knowledge and potential. IQ tests are reasonably valid indicators of academic intelligence, as they predict school success and number of years in school.

Reliability and Validity of IQ tests Qualified validity – valid indicators of academic/verbal intelligence, not intelligence in a truly general sense Correlations: .40s–.50s with school success .60s–.80s with number of years in school

Reliability and Validity of IQ tests Qualified validity They are not good measures of social or practical intelligence and do not measure intelligence in a truly general sense. IQ scores are positively correlated with high status jobs; this may be related to the correlation with school success.

Reliability and Validity of IQ tests Predictive of occupational attainment, debate about predictiveness of performance There is conflicting evidence regarding whether IQ scores predict occupational performance. Court rulings and laws require that tests used in selection of employees measure specific abilities related to job performance.

A test that fails to predict what it is designed to predict lacks Standardization Norms Fairness Validity reliability

A test that fails to predict what it is designed to predict lacks Standardization Norms Fairness Validity reliability

Which of the following is evidence of the reliability of a new intelligence test? A correlation of +0.90 between scores on the new test and on the Wechsler Scale The test predicts ability to succeed in college The correlation between scores for identical twins taking the test is +0.90 Baseline data for test norming are from a diverse sample of 2,000 participants The correlation between scores of participants who take two forms of the test is +0.90

Which of the following is evidence of the reliability of a new intelligence test? A correlation of +0.90 between scores on the new test and on the Wechsler Scale The test predicts ability to succeed in college The correlation between scores for identical twins taking the test is +0.90 Baseline data for test norming are from a diverse sample of 2,000 participants The correlation between scores of participants who take two forms of the test is +0.90

In a normal distribution, approximately what percent of the scores occur within one standard deviation above and below the mean? 5 % 16% 33% 68% 97%

In a normal distribution, approximately what percent of the scores occur within one standard deviation above and below the mean? 5 % 16% 33% 68% 97%

If the variance of a set of scores is 100, the standard deviation will be 5 10 25 50 125

If the variance of a set of scores is 100, the standard deviation will be 5 10 25 50 125

When a teacher compares the performance of her students on the even and odd numbered questions in a multiple-choice test, she is determining Equivalent-form reliability Split-half reliability Face validity Concurrent validity Construct validity

When a teacher compares the performance of her students on the even and odd numbered questions in a multiple-choice test, she is determining Equivalent-form reliability Split-half reliability Face validity Concurrent validity Construct validity

Jay receives a Full Scale IQ score of 125 on the Stanford-Binet Intelligence Scales indicating that he Scored correctly on 125 items on the test Scored exactly at the mode of the test Scored exactly at the median of the test Scored more than one standard deviation above the mean Has 125 units of intelligence

Jay receives a Full Scale IQ score of 125 on the Stanford-Binet Intelligence Scales indicating that he Scored correctly on 125 items on the test Scored exactly at the mode of the test Scored exactly at the median of the test Scored more than one standard deviation above the mean Has 125 units of intelligence

Which of the following is generally true of participants in Lewis Terman’s longitudinal study of intellectually gifted children? Their IQ dropped with age Their IQ increased with age They exhibited a higher-than-average incidence of mental illness They led happy and fulfilling lives They came from larger-than-average families

Which of the following is generally true of participants in Lewis Terman’s longitudinal study of intellectually gifted children? Their IQ dropped with age Their IQ increased with age They exhibited a higher-than-average incidence of mental illness They led happy and fulfilling lives They came from larger-than-average families