Last Week!
Exam Saturday, December 17th, 12 noon
 Do NOT be late!!!
 65 Multiple choice
 5 of 7 definitions
 4 of 7 short answers
 2 of 3 longer answers
 3 hours long
 Short answers and essay CUMULATIVE

Intelligence and Testing: History

Brass instruments in 1800s
– Wundt (1832 – 1920)
– Galton (1822 – 1911)
– Cattell (1860 – 1944)
– Wissler (in 1901)
Testing: History

Advent of the Modern testing
– Attitudes towards mentally ill and mentally
delayed were changing

Alfred Binet
– Developed a scale for the Paris government in
1905
Binet’s scale

Had 4 characteristics:
1. Measured a child’s general mental abilities,
and was aimed at classification, not
assessment
2. Brief and practical
3. Practical judgment was measured rather than
low-level abilities
4. Items arranged by level of difficulty
Examples of items
1. Follows object with moving eyes
3. Grasps item that is seen
7. Points to familiar-named object (point to the cup)
10. Compares two lines of markedly unequal length
18. Reproduces from memory 2 designs shown for
10 seconds
22. Compares 5 blocks to put them in order of
weight
26. Puts 3 nouns or 3 verbs in a sentence
30. Defines abstract words by designating the
difference between them (e.g boredom and
weariness)
Binet continued

1908
– Calculation of mental level
– Standardization

1911
– 5 tests for each age level

1916
– Terman’s influence: people started comparing
ration of mental age and chronological age:

Mental age / chronological age = 100
IQ testing comes to America

Goddard:
– American recruited by Vineland training school
to identify and classify “feebleminded” children
MA and diagnosis of Vineland
Residents tested with a translation of
the Simon-Binet
Binet-Simon
Mental Age
Diagnosis
Number of
Residents
I & II
Idiot
73
III to IV
Imbecile
205
VIII to XII
Feebleminded
100
The Simon-Binet comes to America

Goddard imports test
 Normal sample of 1 547 normal children
yielded 3% of these children were
feebleminded
 His work on Ellis Island in 1910
Group Testing

Army needed a fast way to assess potential
recruits
 Yerkes’ Army Alpha & Army Beta
 Alpha had 8 verbally loaded subtests
Following Oral Directions: mark a cross in the 1st and also
the 3rd circle:
Arithmetical Reasoning: How many men are 5 men and 10
men?
Synonym-Antonym pairs: Are these the same or opposites?
accumulate - dissipate
Number Series Completion: Complete the series:
3 6 8 16 18 36… …
Analogies: Complete the analogy:
Tears-sorrow:: laughter
joy smile girls grin
Group Testing

0 was most common score on Army alpha
Yerkes (1921) calculation of Army
Alpha Data
400
350
300
250
Score 200
150
100
50
0
Test 4 Alpha
0
10
20
30
40
Number of people with score
Group testing con’d

Army Beta designed for illiterates or for
people whose first language was not
English
 Consisted of mazes, mentally counting
blocks, number-symbol completions
Army beta tests
Test 3
O O O O…
X
X
X
X…
OOXOOXOOX…
XXXOXOXXXOXO...
Test 7
Test 4
62
62
59
56
327
327
249
249
1536
1536
3745
3745
45010
45001
62019
62019
Group testing con’d

Very bizarre testing conditions
 Brigham’s misuse of the data
Number of people
Brigham’s (1923) use of Yerkes’ data
150
100
50
0
0
5
10
15
20
25
Score
Nordic
Alpine, Mediterranean
African
History of Intelligence Testing,
summary

Attempts to measure intelligence have been
laden with problems, and the use of the
measures is questionable
 How you develop a test will depend on how
you define and see intelligence
Some Views of Intelligence

Spearman: a general ability which involves
mainly the eduction of relations and correlates
 Binet & Simon: the ability to judge well, to
understand well, and to reason well
 Piaget: A generic term to indicate superior forms
of organization and equilibrium of cognitive
structuring used for adaptation to the physical and
social environment
Definitions of Intelligence



Problems with operational definitions
Layperson’s and expert’s definitions are
similar
Experts agree on 2 part definition:
1. The capacity to learn from experience
2. The capacity to learn from one’s environment
Approaches to Intelligence

Spearman’s g
– Finds high correlations between various subtests
– One general factor (g) and several specific factors (s1,
s2, s3, etc…)
– Invented factor analysis
– Performance due to g and a specific ability on the
subfactors
– g was energy or power in the whole cortex, and the s
factor was a substrate
Cattell

Distinguished between fluid and
crystallized intelligence
 Fluid = nonverbal, culture-reduced, learning
and problem-solving
 Crystallized = Language and world
knowledge
Piaget

Cognitive stages are progression in
intelligence, and process of adaptation is
reflection of intelligence
 Performance on conservation tasks was his
indication of intelligence, had to match age
and stage
Gardner’s Multiple Intelligences

8 criteria for an intelligence:
– Potential isolation by brain damage
– Existence of idiot savants
– Identifiable core operations
– Distinctive developmental history
– Evolutionary plausibility
– Support from experimental psychology
– Support from psychometric findings
– Susceptibility to symbol encoding
Gardner’s Multiple Intelligences

9 intelligences:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Linguistic Intelligences
Musical intelligences
Logical-Mathematical intelligences
Spatial intelligences
Bodily Kinesthetic intelligences
Interpersonal intelligences
Intrapersonal intelligences
Naturalist intelligences
Spirituality/existential intelligences
Information Processing approaches

Like in other cognitive domains, look at
how knowledge base, speed of processing,
working memory, and metacognition affect
performance on tests of intelligence
Scales

Stanford-Binet
– Heavily verbal

Wechsler Scales
– Differs from above in terms of non-verbal items

Kaufman Assessment Battery for children
– Heavily non-verbal and believed to be culture-
fair, and E. has more flexibility when
administering

Bayley scales
– Measures infant intelligence
IQ: Nature or Nurture?

Heritability index
 Evidence for Nature
– Honzik

Evidence for Nurture
– Skeels
– Teratogens
 Fetal alcohol syndrome and Fetal alcohol effect
Differences between groups?

Problems occur when we take previous
arguments and apply them to individual
groups
 Making IQ inherited is making it a
characteristic that is necessarily destined
and immutable
 Started with Cyril Burt, whose work guided
policy in the ‘60s and ‘70s
Differences between groups?

Cyril Burt faked his data
 His defenders were large proponents of
inherent racial differences in IQ, e.g. Jensen
 The Bell Curve by Herrnstein and Murray
The Bell Curve

Relies on faulty statistical analysis
 Relies on work of problematic work of J.
Phillipe Rushton
Racial differences in IQ, con’d

Genetic hypothesis is also untenable for 2
very strong reasons:
– Problems with generalizing within-group
differences to between group differences
– A crucial prediction does not hold up: degree of
ancestry has no effect on IQ (Scarr, 1977)
Intelligence and cognitive
development

Transactional model of development
Environment  Genotype  Phenotype
Phenotype Genotype Environment
There is continuous interaction of child’s
constitution and the environment over time
Example of SES and intelligence

Children from high SES homes have higher
IQ than those from low SES homes
 BUT…SES does not work alone
 Related to home environment, peer group,
academic expectations etc…so could be any
of these things or all of them
Back to Heritability

How much of a trait is there because of
genes?
 Heritability is not independent of
environment (debate is extent of
contribution of each)
Behavioural Genetics

May not be g that is inherited, but rather
aspects of information-processing
– Memory capacity
– Neural transmission
– Durability of memory traces

These develop over time and may be more
susceptible to environmental effects
Behavioural Genetics con’d

Degree of relatedness can predict
heritability of IQ
 Genetics accounts for about 50% of
variance, more so in MZt
 Varies from population to population and
from culture to culture
 More correlated over time
Behavioural Genetics

Large effects of environment also found:
why?
 Nature side looks at correlations…
Correlation of IQ as a function of
Genetic Similarity
Correlation of IQs
0.9
0.8
Parent/ Adoptive
Offspring
Siblings Apart
0.7
0.6
0.5
0.4
0.3
Siblings Together
0.2
0.1
0
Relatedness
Dizygotic twins
together
Monozygotic twins
apart
Monozygotic twins
together
Effects of environment

Nurture side looks at means
 Scarr & Weinberg:
– Disadvantaged children adopted into
advantaged home show big jump in IQ, similar
to their adoptive parents
– BUT IQ still predicted by birth mother’s
education level…
HOW??? – They maintain rank order, but IQ
changes
Effects of early experience

Deprivation in the 1st 2 months of life can
have a detrimental effect on intellectual and
social development
– Institution and War children

Home environment can also affect
intellectual development
– Use of HOME scale
HOME scale

6 subscales to measure type of early
environment child is in
1.
2.
3.
4.
5.
6.
Emotional and verbal responsivity of Mother
Avoidance of restriction and punishment
Organization of physical and temporal env.
Provision of appropriate play materials
Maternal Involvement with the child
Opportunities for variety in daily stimulation
HOME scale

Correlation between score on HOME scale
and Stanford-Binet score at age 2
 Predicts academic performance at age 11
 BUT maintenance depends on child’s future
environment (risk factors)
Interaction of risk factors

Caughy (1996) looked at biological risk
factors (Low birth weight, hospitalization)
and environmental risk factors (low income,
low maternal education)
 Impact of biological risk factors can be
mediated by good home, low environmental
risk factors
More environmental effects…
Maternal behaviours predicts child’s
intellectual development
 Legerstee revisited

Effect of Child
Piaget’s views of child as active
 Child’s behaviour will affect how they are
treated
 Children have personalities, and can control
their environment

Stability of Intellectual
Functioning

Can be changed for the better
– Skeels’ institution study
– Preschool program can help
– Head Start

Can also change for the worse
– Children can lose early benefits if environment
is drastically changed
Back to infants’ DQ

Looking at specific processing skills is
more fruitful than looking at overall
functioning
 Strong correlations found between
infants’ “preference for novelty” and later
IQ
 Suggests an underlying process that child
uses over early years that predicts later
learning
And that, my friends, is cognitive
development…

Remember exam is Cumulative!