The Beginnings of IQ Testing

In 1904, Alfred Binet and Theodore Simon created the first IQ test A new law in France said that all children

had to attend school, and the government wanted a way to identify children who needed remedial help

The Beginnings of IQ TestingFeatures of the Binet-Simon test:

1.Interpreted scores as an estimate of current performance, not innate intelligence

2.They wanted the scores to be used to identify children who needed help, not to label children as smart or dumb

3.Emphasized that training and opportunity could affect intelligence and they wanted to identify areas of performance in which special education could help children identified by the test

4.The test was constructed empirically – based on observed performance - rather than a particular definition of intelligence

The Beginnings of IQ Testing

IQ tests became popular in America in the early 1900s

There was a big increase in immigration and the public wanted a way to classify people

New laws required universal education, and schools wanted a way to determine who could and could not benefit from education

When WWI began, the army wanted a way to separate those who could benefit from military training from those who could not

IQ tests were largely used as a way to discriminate and reinforce prejudices/stereotypes

The impact of culture

on IQ tests

Stanford-Binet Measured different abilities at different levels

Looked at a person’s chronological age vs. their mental age

A common criticism was that the test measured different skills at different ages 2-4 year olds were tested on their ability to

manipulate objects while adults were tested almost exclusively on verbal items While it would be unreasonable to test a very young

child on verbal skills, it is also not appropriate to not test adults on coordination

Stanford-Binet

Another criticism was that the test used the formula:

IQ = (Mental Age / Chronological Age) * 100

A person could have a normal level of functioning for an adult and the numerator would stay constant, but the denominator would increase

Therefore, an elderly person would appear to have an overly low IQ

Theories of Intelligence

Gardner’s Multiple Intelligences:

Linguistic intelligence: Often measured on traditional IQ tests by vocabulary tests and reading comprehension

Logical – mathematical intelligence: Also measured on most IQ tests with analogies, math problems, and logic problems

Spatial intelligence: The ability to mental images of objects and to think about their relationships in space

Gardner’s Multiple Intelligences

Musical intelligence: the ability to perform, compose, and appreciate musical patterns, including patterns of rhythms and pitches

Bodily – kinesthetic intelligence: the ability for controlled movement and coordination, such as that needed by a dancer or surgeon

Interpersonal intelligence: the ability to understand other people's intentions, emotions, motives, and actions, as well as to work effectively with others

Intrapersonal intelligence: the ability to know oneself, to develop a satisfactory sense of identity, and to regulate one’s life

Modern IQ Tests Wechsler Adult Intelligence Scale (WAIS)

Wechsler Intelligence Scale for Children (WISC)

Results on these tests are highly correlated with academic performance and

achievement

These tests measure skills that are assumed to be components of intelligence and on a

variety of tasks

IQ Tests use a mean of 100, standard deviation

of 15

WAIS and WISC

These tests assess two forms of intelligence: Verbal and

Performance

Verbal ScalesVerbal Comprehension

Index

Vocabulary Receptive and expressive vocabulary Ex. defining words

Similarities Verbal abstract reasoning and

conceptualization abilities Ex. How are a snake and alligator alike?

Similarity Examples

Which letter on the right belongs to the same category as the one on the left?

1.J A M S Z T

2.A S D U V X

Similarity Examples

Which letter on the right belongs to the same category as the one on the left?

1.J A M S Z T

S, because it’s the only letter with a curve in it

1.A S D U V X

U, because it’s the only vowel

Verbal ScalesVerbal Comprehension

Index Information

Similar to trivial pursuit Measures knowledge of factual information,

and strongly influenced by culture

Comprehension Understanding of social conventions and

common sense Also culturally loaded – ex. “What should

you do if you find an injured person laying on the sidewalk?”

Verbal ScalesWorking Memory

Index Arithmetic Mental performance of mathematical word problems Measures attention, concentration, and numeric reasoning

Digit span Requires the repetition of number strings forwards and

backwards Measures concentration, attention, and immediate memory People with attention deficits or anxiety tend to get lower

scores

Letter – number sequencing Ex. Repeat the sequence Q-1-B-3-J-2, but place the

numbers in numerical order and then the letters in alphabetical order

Performance ScalesPerceptual

Organization

Picture completion Requires recognition of the missing parts in pictures Measures visual perception, long term visual memory,

and the ability to differentiate essential from inessential details

Performance ScalesPerceptual

Organization Block design

Considered one of the strongest measures of nonverbal intelligence and reasoning

Colored blocks are put together to make designs

Performance ScalesPerceptual

OrganizationMatrix reasoning

Untimed test which measures abstract nonverbal reasoning ability

Consists of a sequence or group of designs and the individual being tested is required to fill in a missing design from a number of choices

Performance ScalesProcessing Speed

Digit Symbol coding Symbols are matched with numbers or shapes

according to a key The individual is asked to put the appropriate symbol

under digits in a sequence based on the key Measures visual – motor speed and short term visual

memory

Performance ScalesProcessing Speed

Symbol search

The individual scans images and determines whether a target symbol is in that array

Performance Scales

Picture arrangement Requires that pictures be arranged in order to tell a

story Measures nonverbal understanding of social

interaction and ability to reason sequentially

Object assembly Consists of jigsaw puzzles Measures visual-spatial abilities and ability to see how

parts make up a whole

Learning Disabilities

Discussion

Learning Disabilities

Learning disabilities are defined by a disturbance in a skill that significantly interferes with academic achievement or activities of daily living that require that skill

Wechsler said that a learning disability should be diagnosed if scores on performance scales are more than 15 points (1 standard deviation) apart

Learning Disabilities

Learning disabilities do not mean that the person is stupid

For example, on page 5 of the handout note that in the August 1998 testing the verbal IQ is 130 – two standard deviations above the mean and in the 98% percentile

The performance IQ is 110 – in the high end of the average range and the 75% percentile

Problems with the WAIS

Vocabulary and general knowledge rely heavily on educational background rather than ability

Comprehension – there is not necessarily a right or wrong answer, more than one answer may be logical

Problems with the WAIS

For example, the question “What is the thing to do if you find an envelope in the street that is sealed and addressed and has a new stamp?” The correct answer, worth 2 points, is to mail it

or bring it to the post office The score drops to 1 point with the answer of

recognizing that it belongs to someone else and giving it to a police man

Suggesting opening it because there may be money in the envelope is a score of zero points. It is not an inherently “wrong” answer and does suggest a form of logic, but it is socially unacceptable

Problems with the WAIS

Examiners are supposed to treat all people taking the test the same, but it is impossible for the test to be exactly the same every time

Some examiners may ask the person taking the test to explain an answer (especially on the comprehension part), others don’t

Historically, black people score better on IQ tests when the test is given by a black examiner