Chapter 9Intelligence &

Psychological Testing

Principle Types of Tests• Standardized measure of a sample of a persons behavior

• Represent a sample of your behavior

A) Mental ability- intelligence: measures general mental abilities- Aptitude: assess specific types of mental abilities- Achievement: gauge a persons mastery and knowledge of various subjects

B) Personality test- measure various aspects of personality- also called scales b/c there’s no right or wrong

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Aptitude and Achievement Tests

Aptitude tests are intended to predict your ability to learn a new skill and achievement tests are intended to reflect what you have already learned.

Standardization & Norms• Refers to the uniform procedures used in the

administration and scoring of a test.

• Test norms: illustrate where your score falls in comparison to other scores

• Percentile score: indicates the percentage of people who score at or below the score one has obtained

• Sample of people that the norms are based on is called a tests standardized group or norm group

The Normal Curve and Stanford-Binet IQ Scores

IQs less than 70 = mental retardation. More than 130 = gifted

Flynn Effect

Reliability• Repeated measurements should yield reasoning similar results

• Split-half Reliability: Dividing the test into two equal halves and assessing how consistent the scores are.

• Reliability using different tests: Using different forms of the test to measure consistency between them.

• Test-Retest Reliability: Using the same test on two occasions to measure consistency.

• Should fall b/w .70-.90

* Correlation coefficient: is a numerical index of the degree of relationship b/w two variables

Validity• Ability of a test to measure what it was designed

to measure

A) Content validity: content of a test is representative of the domain its supposed to cover

B) Criterion-related validity: estimate participants score w/ independent criterion

C)Construct validity: the extent to which evidence shows that a test measures a particular hypothetical construct

Influential People• Francis Galton: believed intelligence was hereditary

- measured intelligence by our senses

• Alfred Binet: devised the first test to measure students mental abilities in 1905- mental age: he or she displayed the mental ability of a child

of that actual age

• Lewis Terman and colleagues @ Stanford:

• David Wechsler: published the first high-quality IQ test for adults in 1939 (WAIS: Wechsler Adult Intelligence Scale)

IQ= Mental age/Chronological age X 100

IQ examsQ & A

1. What kind of questions?- vary depending on the age of subjects- WAIS: recognize vocab, figure out patterns, and basic memory

2. What do modern IQ scores mean?- bell curve: normal distribution- deviation IQ cores: locate subjects precisely within

the normal distribution, using standard deviation as the unit of measurement- IQ tests set SD @ 15

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Bell CurveStandard Deviation

More Q & A3. Do intelligence test have adequate reliability?

- correlation in the .90’s- the question of extraneous variables

4. Do intelligence tests have adequate validity?- purpose: to predict school performance- school grades & IQ scores .4-.5

5. Do intelligence tests predict vocational success?

6. Are IQ tests used in other cultures?- do not translate well into non-western cultures- might value different mental skills & have a different concept of intelligence

Mental Retardation

• Sub average mental abilities accompanied by deficiencies in adaptive skills, originating before age 18

• Cut off point has changed 4 times

• Levels:1. 2-3% of school aged children2. mild: 51-70 sixth grade by late teens3. moderate: 2nd-4th grade4. Severe: limited speech toilet

habits5. Profound: little to no speech,

not toilet trained; relatively unresponsive to training

Robert Stenberg• Conducts study surveying what people considered

intelligent

1. Verbal - verbally fluent- speaks clearly- knowledgeable about a particular field- reads w/ high comprehension

2. Practical- sees all aspects of a problem- makes good decisions- poses problems in an optimal way

3. Social- accepts others for what they are- thinks before speaking- sensitive to other peoples needs & desires

Giftedness• most school districts consider children who fall in the upper 2-3% of the IQ distribution to be gifted

• stereotyped as weak, sickly, socially awkward

• Terman’s longitudinal study: breaking the stereotypes

• Emily Winners study comparing gifted students falling from a 130-150 and profoundly intelligent (150-180)

Gifted Achievement• three ring conception of eminent giftedness

- need these three in order to achieve new heights as adult

• question of those who work hard being considered geniuses

Hereditary Influence on Intelligence

• b/c those that share genes probably share environments we must look into twin & adoption studies

• Twins- compare fraternal vs. identical- studies prove that intelligence is inherited

• Adoptive studies- correlation w/ parent over .20

• Foster Care- those who were raised in poverty did not advance intellectually as other kids- those that were switched from fosters homes in poverty increased their IQ scores by 10-12 pts

Cultural Differences

• Minority groups fall below whites by 3-15 pts

• If studies showed that genes dictates intelligence than are there races that are less intelligent?

• Minorities are often raised in lower social classes

• Lower class scores are below by 15 pts even when studying just whites

Spearman’s g theory• Factor analysis: correlations among many variables are analyzed to

identify closely related clusters of variables

• G= general ability- peoples special abilities are determined by their general ability

• Thurstone– Carved mental abilities into seven factors = primary mental

abilities ( word fluency, verbal comprehension, spatial ability, perceptual speed, numerical ability, inductive reasoning & memory)

• g should be divided into- fluid intelligence: reasoning, memory, speed of info processing- crystalized intelligence: ability to apply knowledge & skills in problem solving skills