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Use and Abuse of Intelligence Testing

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Broca’s Craniometry

Men were more intelligent because they had larger brains

The difference between contemporary men and women’s brains was greater than between prehistoric men and women

Why? Evolution – men more involved in a competition for survival – they had to adapt quicker and be more intelligent

Opinion widely accepted and led to global discrimination of women in education that lasted for nearly a century

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Broca’s Craniometry (cont.)

These “findings” influenced by prevailing beliefs of the time

He looked for explanations that were consistent with the beliefs

Commonly believed that younger adults more intelligent than older, Primitive people less intelligent than modern people, and women less intelligent than men.

Needed to find a reason – brain size

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Mismeasurement of Man

Re-examined Broca’s data When age differences accounted for

difference between men and women reduced to 113 grams instead of 181

Prehistoric data based upon 13 brains – very small sample

Body size not taken into account

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Alfred Binet

1st objective and standardized form of intelligence testing

Binet studied hypnotism with Jean Charcot

Self-taught psychologist and demonstrated poor critical thinking skills – accepted without question the views of people he thought were smart

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Binet and Fere

Use of hypnotism and magnets The action on one side of the body of a

hypnotized person can be moved to the other side by moving a magnet

Under hypnosis a person’s motivation and perception could be changes to the opposite using a magnet

Problem – no one could replicate his results

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Binet and Fere

Experiments poorly done with little controls

Libault reported that Binet’s results were the result of suggestion, subjects knew what they were supposed to do

Binet proved wrong when Libault and others showed that Binet’s results could occur without magnets

Binet forced to admit that he and Charcot were wrong, hypnosis and hysteria not linked to a deteriorating nervous system

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Binet and intelligence testing

Given the task of developing an objective assessment of children that could identify those who would need help to perform in a normal classroom

1906 – Binet and Simon developed the Binet-Simon Scale of general intelligence

Test began to be given under very controlled situations to determine its validity

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Testing validity

Identify two groups a normal group and an abnormal group

Give each group the test

Identify which tests items differentiate the 2 groups – on which items did the 2 groups consistently perform differently

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Binet-Simon Scale of Intelligence

Purpose was to identify children who would need help

Based on 2 assumptions of Binet Intelligence not a unitary ability, but a

combinations of many abilities Inheritance may place a limit on

intelligence, but no one reaches their full potential therefore everyone can grow intellectually

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1908 Revised Binet-Simon Scale

Mental level included – a 5 year old should perform at a 5 year old level

Mental level was changeable- a strong environmental position

Strongly opposed the idea of the Intelligence Quotient (IQ)

IQ developed by Louis Stern (1912) Concept of mental level evolved

into mental age – opposed by Binet

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Spearmen’s general intelligence

Intelligence a unitary ability and inherited

American’s accepted Spearman’s perspective of intelligence

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Binet – Simon scale introduced to the U.S.

1911 version brought to the U.S.

Principally by Henry Goddard and Louis Terman

Goddard face by the same problem in New Jersey as Binet faced in Paris

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Henry Goddard

Took Spearman’s innate perspective to intelligence and used his English translations as tests

Heavily influenced by Mendel’s study of heredity in plants

Study of the Kallikac family

Supported concept of eugenics and helped lead to forced sterilzation of people determined to be mentally deficient

Study seriously flawed

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Goddard and the Vineland School for the Feebleminded

Tested his English translation of the Binet-Simon scale using children in the Vineland School and compared them to children in public schools

The 2 groups of children scored very different so he concluded it was a good test

Ignored important result ignored

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Goddard and immigration

More people from southern and eastern Europe immigrating to the U.S.

Method needed to screen new immigrants to exclude mental deficients

Goddard “showed” that the Binet test could identify people with mental defects. Thousands excluded because they failed the test

Test used made up of questions only a U.S. resident would be likely to answer

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Later Goddard

Began work with gifted children that was followed up by Terman

Gifted do not end up maladjusted and that enriched programs can help them

Rejected his previous view of intelligence and adopted Binet’s , but the damage had been done

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Louis Terman

Intelligence inherited

Low intelligence the cause of all criminal and immoral behavior

Modified the Binet test to the Stanford-Binet

Showed the Stanford-Binet correlated with academic success

Extensive work with gifted children – longitudinal study of Terman’s Termites

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Louis Terman’s longitudinal study

Findings: Most children excelled in school and later excelled in

college Most were highly successful professionally- making

many professional contributions Problems:

Sample unrepresentative of the population They knew and were repeatedly told how special

they were Very few comparison’s with a control group Terman helped many of them with scholarships and

letters of recommendation No really great leader, scholar, or scientists were

among them

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Robert Yerkes

Army intelligence tests – used to test army recruits and draftees

Purpose: To segregate the mentally incompetent Classify according to mental ability Identify those most competent for special training

Characteristics of test Group testing Intelligence independent of education Challenging to brightest but could be taken by those

of lesser ability Toke less than an hour to take

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Results of Army Alpha and beta Tests

Reported to be the greatest thing to come out of psychology

Psychology and psychologists status as a science grew tremendously

Problem average score on the test was below normal – the idiot level - adults scoring at the 13 year old level

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Impact of the army test

Edison did his studies of American intelligence and found people to be “amazingly ignorant”

Poor scores blamed on the deterioration of the national intelligence due to immigration of certain ethnic groups and reproduction of inferior people

Resulted in further immigration restrictions and sterilization

No one questioned the validity of the test and the testing conditions

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The challenge to Goddard, Terman , and other psychologists

!922 Horace English – data from test were misread

1923 – F. N. Freeman – mental testers conclude that thereis no way to compare intelligence of peopleof different upbringing

Walter Lippmann in 1922 and 1923 The average adult intelligence cannot be less than the average

adult intelligence Average intelligence on the Stanford-Binet was at a 16 year level

on the army test it was 13 Supported the original ideas of Binet and highly criticized later

psychologist

Terman tried to respond to Lippmann’s articles, but should have known better than debate a great journalist in a public forum