Intelligence
•	General or specific
•	Important or worthless
•	Genetic or environmental
•	Group differences
•	Implications
Is intelligence general or specific
•	Both
•	Most abilities and attributes are like that
–	Consider athletic ability
–	Or even reading ability
•	Notion of “G”
Diagram of “G”
Specific intelligences -Thurstone
•	Verbal comprehension
•	Word fluency
•	Number calculation
•	Spatial reasoning
•	Associative memory
•	Perceptual speed
•	General reasoning
Specific Intelligences – Gardner
•	Linguistic
•	Logico-mathematical
•	Spatial
•	Musical
•	Bodily-kinesthetic
•	Intra-personal dealing with self knowledge 
•	Inter-personal knowledge
Specific intelligences – Sternberg
•	More a process theory, how people use their abilities
•	Componential
–	Meta-components which basically outline problems, plan, monitor, regulate performance
–	Knowledge acquisition, combining information in new and creative ways
–	Performance -- actually using various cognitive processes in an efficient and speedy manner
–	Experiential – how we use and learn from experience
–	Contextual – applying intelligence in the real world which offers situations that vary in their intellectual demands
Sternberg’s three types of intelligence
•	Analytic 
–	Math
–	Verbal
–	The standard measures
•	Practical 
–	Using knowledge for concrete problems
–	May rely on analytic
•	Creative 
–	Fluid intelligence
–	Novel solutions
Emotional intelligence or EQ
•	Developed by Salovey and Goleman
•	Has several components
–	Understanding one’s own emotions
–	Using them productively
–	Controlling and delay of gratification which has become the key concept
Is Intelligence important – The Bell Curve
•	Gigantic review of literature on correlates of IQ with special focus on a national longitudinal survey
Bell Curve – Social Class
•	Social class now a function of IQ
–	In former eras class was inherited 
•	Right schools
•	Right contacts
–	In the present era we are creating class based on intelligence.
•	Admission to college
•	Income tied to jobs where IQ make a big difference
IQ predicts success
•	IQ is related to income and status
•	These correlations are both within and between professions
–	Obviously between
–	But within a profession even for those professions which are generally manual or blue collar
Bell Curve – Other correlates
•	Moreover IQ is strongly related to social indicators
–	Poverty
–	Crime
–	Welfare
•	Multiplier effect
–	Relatively less intelligent people have worse living conditions
•	Assuming that affects IQ
•	Thus produce intellectually toxic environments
Correlates of IQ
Disentangling heredity and environment
•	Assume that IQ is mostly inherited
•	But also related to social class, so poor kids have disadvantages
•	How to separate
–	Look at IQ controlling for parental social class
–	And SES controlling for IQ
–	If IQ (inherited) is crucial then controlling for SES should make no difference
–	But if SES is crucial then controlling for IQ should make no difference
Unemployment & IQ
Poverty and IQ
Bell Curve – Race
•	A small part of the book is also devoted to race effects
•	They argue that race differences in IQ are reduced but not eliminated when one takes social class into account
•	And while they are somewhat agnostic they claim that the best present evidence is that race differences are likely to be at least partially, and they believe largely, due to genetics.
The genetics of intelligence
•	Clearly a genetic component
•	Twin studies
•	Adoption studies
•	Probably about 50-60% of the variance explained by genetics
Also some brain differences
•	Brain differences might support genetic differences
•	Brain size greater in more intelligent – only some areas
•	Smarter people process some sorts of information more rapidly
–	Frontal lobes
–	Working memory
•	But cause and effect problematic
Environmental factors
•	Sometimes substantial gains with dramatic environment improvement
•	Formal schooling improves
•	Flynn effect
–	IQ does up 3 points every decade
–	Perhaps due to better schools or more environmental challenges
•	But generally environment has no dramatic effects
The heredity – environments controversy
•	Hard to disentangle the two
•	Worry about that we can affect – the environment
•	Keep in mind that if everyone had the same environment then heredity would be the only thing that produced human variability
Group differences
•	Asians score higher than whites
•	Jews score higher than gentiles
•	Whites score higher than blacks 
–	About 15 points or 1 sd
–	Means that 16% of blacks score above the white mean
•	Hispanics are generally between whites and blacks
•	Native Americans usually below blacks
Are such differences genetic
•	Could be genetic
•	But variability among people in not the same as group differences
–	The fertilizer analogy
•	We simply don’t know whether group differences are partially genetic 
–	The Jensen Report argument
–	Better to assume not – simple pragmatism and values
–	And shouldn’t worry about the possibility
Are tests culturally fair?
•	Often assumed that the tests are unfair to people on non-white middle class backgrounds
–	The cello item
–	Motivation to do well
•	However this is not a complete explanation
–	No one has devised a culture fair test that is valid
–	Eliminating items that are obviously biased does not change differences
•	No evidence that minorities are generally less motivated to do well
What about testing effects
•	Stereotype threat
•	Minorities do somewhat better when tested by members of own group
–	But these effects are quite small
Other environmental effects
•	Differences in child-rearing
–	TV watching
–	Commands versus explanations
•	Inferior schools
•	Nutrition
•	Pre-natal care
•	Lead poisoning and other pollutants
What about IQ
•	It is important especially as world becomes more complex
•	But for most things it may be less important than motivation and luck
•	For most purposes not important to know
–	Teachers?
–	Parents?
–	Who needs to know IQ?