week 9 - intelligence Flashcards
intelligence definition is disagree among psychologists but what are some aspects that are agreed?
Perkins 1995 -
- Relates to mostly cognitive skills
- Includes the ability to learn and solve problems
consensus definition?
- very general mental capacity that among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly and learn from experience.
It reflects a broader and deeper capability for comprehending our surroundings. - catching on, making sense, figuring out
what do / don’t we measure with intelligence testing?
NOT -
- spacial perception
- reasoning ability
YES -
- the capacity of an individual to understand the world about him and his resourcefulness to cope with it’s challenges
Intelligence - a latent concept?
Scientific notion of intelligence derives initially from psychometric instruments that predict performance in school
Therefore what is intelligence inferred from?
The relationship between test scores and other criteria
what are the origins of intelligence testing?
Alfred Binet & Theodore Simon
- Developed a test of ‘mental age’ (Binet-Simon test) in 1905
- Aimed at identifying students who needed additional help
- Tasks included:
Following a lit match
Coin counting
Defining words
Naming objects in pictures
what is mental age?
The age an average child can complete a particular test item
- Test items can be arranged in terms of the mental age required to complete each item
- Difficulty level completed in one type of task usually mean the child can complete another type of task to a similar level of difficulty
how is mental age measured?
- 30 items in increasing difficulty, with every six items corresponding to one age group
- Level 3 (corresponding to 3 year-olds): following movement of a match, pointing to nose etc.
- Level 7 describing a picture, completing a sentence
- Score: if answer correctly on all questions in level 7 + 3 (out of 6) in level 8, mental age (ability) = 7.5
what is the Stanford-Binet test
Terman developed in 2016.
- tasks for specific age group
- Terman used ratio of Mental Age to Chronological Age to calculate IQ
IQ - numbers and limitations?
Stern 1912 - if mental age and chronological age are the same then IQ 100
Useful when child is young but as mental ability does not develop at the same rate after 16–18 years old, this is not useful
Deviation IQ was proposed by Wechsler (1975) to remedy this limitation
Deviation IQ
Person’s performance relative to their peers
Average person is given an IQ score of 100
Scores above & below are scaled to give a Standard Deviation of 15
95% of scores are within 2 SDs of mean (between 70 – 130)
What are the issues with intelligence testing?
How do we know something is testing intelligence if there is disagreement about what it is?
Some theories say memory is part of intelligence some do not
what about different skills?
Is everyone equally good at things IQ tests measure?
Arithmetic
Verbal comprehension
Picture completion
Tests (e.g., Binet-Simon) are abstract; what are they assessing?
Controversial – lots of disagreement!
Explanations / theories (based on the same data) diverge
Different views?
Large source of debate amongst intelligence theorists
Unitary view = that intelligence is ‘one thing’
Unitary theorists argue that even different tests are usually correlated
Multi-factorial view = that intelligence is made up of multiple factors
Argue that intelligence varies by test so must be multi-faceted
Spearmans ‘g’ factor
Different scores on different intelligence tests but they have an ability in common
The ‘g’ factor (general intelligence factor)
The scores on specific aspects – ‘s’ factors
We can assess ‘g’ with one test which assesses these ‘s’ areas
‘g’ is a better measure of IQ than scores on any individual ‘s’ factor
what did Spearmans research find?
People who do well on one ability measure, tend to do well on others
There were positive correlations between scores on different tests
Used as evidence that there must be one common underlying factor/ability
Spearman and factor analysis
Tests may not seem valid/internally reliable if there are different elements
Statistical technique called ‘factor analysis’ used to find Spearman’s ‘s’ factors
how does Wechsler measure ‘g’
Wechsler devised the Wechsler Adult Intelligence Scale (WAIS, 1955) & the Wechsler Intelligence Scale for Children (WISC, 1949)
Each scale assessed ‘g’ and comprised two sub measures: Verbal and Performance
Some questions rely on culture (e.g. vocabulary) – difficult to test overall ‘g’
Measuring ‘g’: Raven’s Progressive Matrices
Designed in 1938
Measured ‘g’ as an abstract ability
RPM minimised influence of culture by relying on non-verbal problems
Comprises 60 items
Thurstone’s (1938) Primary Mental Abilities
Thurstone disagreed with ‘g’ as a solitary factor
Employed factor analysis on over 56 tests and found not one but seven separate factors, or intelligences
Labelled these ‘primary mental abilities’
Intelligences operated independently of each other, i.e., you can perform well on one factor/ability yet perform poorly on another
what are the primary mental abilities?
Spatial
Perceptual speed
Numerical ability
Verbal comprehension
Word fluency
Associative memory
Reasoning
Cattell’s (1967) “crystallised and fluid intelligence”
Cattell gathered evidence from conducting factor analyses
Found support for two distinct types of intelligence, rejecting a single ‘g’ factor:
Crystallised intelligence (Gc)
Acquired skills and knowledge gained through experience
Increases with age and experience
Fluid intelligence (Gf)
Basic information processing and abstract thinking ability
Present from birth, stabilises in adulthood, decreases in old age
Evidence for Gc and Gf
general ability (g) accounts for <50% of variance in performance on a series of diverse tests (Carroll, 1993)
How do we explain the remaining 50% of performance?
Genetic differences underlie Gc and Gf (Christoforou et al., 2014)
Gc and Gf are related to different brain regions (Barbey et al., 2012)
BUT Gc and Gf share ~50% genetic variance (Wainwright et al., 2005), so how different are they really?
Is intelligence heritable?
Controversial history – Galton, eugenics
More recent work suggests IQ (or g) is heritable ~50%
Heritability = statistical technique for estimating how much of the variance in a trait can be accounted for by genetics difference between individuals
The heritability of g increases as we age
Focus on literacy & numeracy in early years education may work to level the playing field from the environmental perspective
As we age, we select our own environments
Selected environments correlate with ‘g’-related propensities (practice effect)
Gardner’s (1983) Multiple Intelligences
Rejected established ideas of intelligence
Mathematical, linguistic, logic
Intelligence should involve all 5 senses
Proposed 7 ‘intelligences’
Favoured practical activities to assess intelligence
Rejected traditional IQ tests
In 1996, added:
naturalist intelligence
&
existentialist intelligence
