Intelligence

Alfred Binet - 1905

• Worked with Theodore Simon to develop tests of intelligence

• Believed in “higher” mental processes → memory, problem solving, language, judgements

  • Developed tests to examine these skills

• Believed in the idea of mental age

• Brought to North America by Louis Terman

  • Became more politicized, more innate based thinking of intelligence

Intelligence Testing: Stanford-Binet Intelligence Test

• Mean score of 100 if you are acting at your mental/chrono age

  • Originally used intelligence quotient (mental age/chronological age x 100)

  • Scores now given based on deviation– where a child scores relative to the average at their age

    • Mental age isn’t applicable once you get to adults, thus why we rely on deviations

• Initially provided 1 general score, now also provides sub scores

Intelligence Testing: Wechsler Intelligent Scale for Children (WISC)

Criticized that Stanford Binet test was biased towards kids vocabulary and language abilities, over-relied on vocabover-relied

• Provides general score plus 5 composite scores

  • Ages 6-16

• There is also wechsler preschool and primary scale of intelligence (WPPSI)

  • 2.5-6 years old

Involves alot pattern detecting, not relying on verbal abilities, less language based

Most common tests to use on children

Reliability (Intelligence testing)

Refers to consistency

• Split-half reliability

  • Measuring if first half and second half of test show the same scores

• Test-retest reliability

  • Is the test/score consistent if you are given it multiple times

  • People who do better earlier in life on IQ tests, do better later in life on IQ tests

Validity (intelligence testing)

Are these tests an accurate valid measure of what we think intelligence is?

• Content & Construct Validity

  • Does content of questions relate to what we think intelligence is? (specific questions)

  • Is this test a good measurement of the construct of intelligence? (overall construction of test)

• Predictive validity

  • Do tests predict real world performance?

    • High Iq tests are highly correlated with training success in military, job performance of high complexity jobs

Lack of Bias (intelligence testing)

Should be equivalently accurate at measuring intelligence across all backgrounds

• Content-validity bias

  • Is the content equally relevant to all participants to measure IQ?

• Predictive-validity bias

  • Are these equally predictive of IQ across all groups?

Psychometric Approach

Intelligence operationalized as –> IQ Tests

• These tests measure what they test

Not an agreed upon conception of what intelligence is**

Defining Intelligence: General Intelligence (g)

General intelligence as multiple abilities/processes

• “People who are good at math are also good at science and English and other subjects”

General Intelligence is comprised of:

• Crystallized Intelligence:

  • Factual knowledge

    • Knowing who George Washington is, hamburgers are hot…etc

  • Crystallized knowledge grows with age

• Fluid Intelligence

  • Ability to solve new problems, think on the spot

  • Fluid intelligence declines with age

This theory suggests that people who have higher levels of crystallized intelligence, should have high levels of fluid intelligence

• Also talks about sub abilities/sub component scores: visual perception, audio perception

  • But all of these sub abilities correlate back into overall general intelligence

Defining Intelligence: Multiple types of intelligence

• Sternberg’s Theory of Successful Intelligence

  • Analytical Intelligence

    • Problem solving ability

    • What IQ tests usually test for

  • Creative Intelligence

    • Can you come up with new solutions?

  • Practical Intelligence

    • Street smarts

      • Can you adapt on the spot if entering a new neighbourhood, city?

• Gardner’s Multiple Intelligences

  • 8 or more different types of intelligence

    • Musical, bodily-kinaesthetic, interpersonal, verbal-linguistic, logical-mathematical, naturalistic, intrapersonal, visual-spatial

  • Has been influential in educational settings

No best one theory that is agreed upon

IQ Scores: Individual Differences

• Genetics

  • Fraternal vs Identical Twins: MZ twins more similar in IQ as they get older, whereas DZ twins IQ become more dissimilar with age

    • Choices they make to match their genetic tendencies… active effects

  • IQ and Genetically, Environmentally related or both: The more similar genes are, the more similar IQ scores are

• Gene-environment correlations

  • Passive effects: Parents create an environment that also fits the genetic tendencies of child

    • E.g parents who like reading alot have books in their house, thus kids can read more and learn more reading skills/vocab

  • Evocative effects: child has genetic tendency to evoke an environment that fits their genetic tendency

    • e.g. Child talks alot and talks at grocery store and more ppl will talk back to them, thus increasing there communication skills

  • Active effects: Childs genetic tendency leads them to actively select things int their environment that fits their genes

    • e.g. Kids stronger in math asking for harder math assignments

IQ Scores: Individual Differences (Environment)

• Schooling

  • Being in school is associated with higher IQ scores

• Family/home environement

  • Parents who are more involved/talked more to their kids = higher IQ scores

• SES

  • Higher SES = higher IQ

• Time Period

  • IQ continues to rise over the years/decades

IQ Testing Today

• Administered and scored by trained professionals

• Very strict guidelines

• Most tests are continuously re-normed

  • For the population being tested (ie, a culturally diverse Canadian-based sample)

  • To re-determine what an IQ of 100 means (vs 70 vs 130 vs…)

• In some regions/schools, used to quality for…

  • Learning disability diagnosis and access to supports

  • Access to special education classes

  • Access to giftedness programs and supports

• Sometimes used in court cases, policy

  • Example: death penalty in US

IQ scores are correlated with many other variables

• Job performance

• Attitudues

• Health

• Mortality

• & others

Can IQ be used as a tool for research and policy decisions?

Yes

• E.g. IQ & Lead

Old belief: only large amounts of lead exposure are toxic

Research –> even small amounts of lead is associated with a drop in IQ

Led to policies banning in gasoline!

What other changes/differences in IQ can/have be used to study the impacts of?

• Poverty

• Exposure to violence

• Pollution

• Breaks from school

• Etc

Is it certain that IQ tests only measure intelligence?

• IQ tests may not actually measure “intelligence”

  • Test performance is sensitive to motivation ($$ incentive), to coaching

    • Suggests your score may not be innately influenced but more so by motivation?

  • Bias in testing

    • Cultural differences, certain tests white people get more correct because it’s more common in their culture (e.g. a regatta)

Problem of IQ Testing

we tend to interpret IQ scores as evidence of a person’s underlying mental ability...

not as evidence of their cultural knowledge, motivation, coaching, stress that day, hunger, etc

History of IQ testing and Eugenics

History of IQ tests being used and
developed for eugenics

• ”The science of improving stock” (Galton) → the idea that heritable human characteristics should be controlled, through breeding, to improve the human species

• IQ tests used to sort

  • Created racial hierarchies in armies … extended into society

• IQ tests used for policies on forced sterilization, restrictions on marriage, etc

  • E.g. Leilani Muir… didn’t know she was forcibly sterilized because of her IQ

Interpreting group differences in IQ scores (Dangerous use continued)

• Gender → spatial abilities

  • Women perform worse than men

  • This gender difference only shows up ages 6-7, prior there is no difference

• Race

  • White individuals score higher than Black individuals (10pt difference)

• Have been interpreted in terms of “genetic advantage” for higher-scoring groups

  • Not accurate science!!!
    Race is socially (not genetically) constructed

Why racial group differences in IQ tests?

Social class differences?

Culturally biased tests?

Stereotype threat?

Stereotype Threat Gist

• We belong to social groups associated with stereotypes related to intelligence.

• Our awareness of these stereotypes can impact our thoughts and performance

A psychological burden caused by the concern that one’s performance
or behavior might confirm a negative stereotype about one’s group.

Mechanisms of Stereotype Threat

Know all steps/factors that lead to impaired performance

Ambady et al Stereotype Threat Study

• Studied asian American girls and math performance

  • Conflicting stereotypes +/-

• Condition 1: girls are primed with their Asian identity

• Condition 2: girls are primed with gender identity

Results:

• Priming asian identity = better math scores

• Priming girl (gender) identity = worse math scores

  • Except perform better in upper elementary

Details of Picho & Schmader Stereotype Threat Study

When do Gender Stereotypes Impair Math
Performance? A Study of Stereotype Threat among Ugandan Adolescence

• Extending research on stereotype treat beyond WEIRD populations

• Examine how expectations of others holding gender stereotypes and own endorsement of gender stereotypes contribute to stereotype threat

(Uganda typically relies less on gender stereotypes)

Picho & Schmader Ugandan Girls Math Study Conditions

Picho & Schamder Ugandan Girls mAth Scores Study Results

• Stereotype threat present only when participants expected that the test-giver held gendered expectations

  • Same pattern for both girls and boys

• Perhaps differences in how stereotype threat impacts us across age/culture are due to when and whether we become aware of stereotypes...
  

People are acting according to what they believe the test-takers gendered beliefs are

Intelligence Mindsets

• Predicts response to challenges, failure

• Associated with academic outcomes

• Growth mindset taught through intervention → linked with better
  academic performance

Fixed Mindset (Entity Theory)

Intelligence and talent are fixed at birth

Growth Mindset (Incremental Theory)

Intelligence and talent can go up or down

• Controversy becuase not all studies find that growth mindset is linked with better performance…

• Are there differences in who growth mindsets might be beneficial for?

Intelligence & IQ testing: How might we improve IQ test?

Improvements in the test structure/design?

• Efforts to counteract stereotype threat

• Dynamic assessment –> goal is to examine learning potential, test how much a child can learn with assistance

Shift how we think about IQ?

• How IQ scores are interpreted

Sun et al Article DETAILS

Are there cultural differences in mindsets and in the association between mindsets and better academic performance?

• In China, the belief of intelligence as due to “innate” ability?

• Compared to US, Chinese youth more likely to link learning/achievement to “purposes of life”, working hard, vs determined by intelligence?

Sun et al RESULTS

Are there cultural differences in mindsets and in the association between mindsets and better academic performance?

• Growth mindset more common in US

• Fixed mindset more common in China

• In china, mindset about intelligence has no relationship with academic performance

• In USA, mindset is associated with performance

  • growth mindset associated with better performance

Intelligence Mindsets across cultures

• Differences across cultures

• More impact for low-achieving students

• When teachers and peers are also supportive of growth mindset beliefs

• When contexts allow for growth!

Standard Deviation

A score of 100 means you match the average of your age group

• 1 SD above means 115

• 1 SD below means 85

68% of individuals are within 1 SD from the mean

How can we tell if an IQ test is a good measurement of intelligence

Reliable, Valid, and lack of bias