Lecture #7: Stereotype Threat I
o 0.47 = correlation between parent and child’s intelligence
o Thus, intelligence is highly heritable
o IQ of identical twins, even when raised apart, are highly related. As compared to
o IQ of adopted child is much more related to the bio mother.
o IQ of identical twins reared apart are less relate in IQ than those raised together
o IQ of fraternal twins are more related than regular siblings. Both share 50% of
their DNA but, fraternal twins share more environment with each other than reg
o IQ of adopted children with diff mothers living in same enviro is more similar than
unrelated individuals reared apart
o Impoverished enviro relates to lower IQ
• Nature vs Nurture
o Both clearly play a role
o Heribality is roughly half (i.e. roughly half of the variance can be attributed to
genes, may even be closer to be 0.65)
o But, if within-group has a gene component, between should have that too????
The answer is no
Between group diffs may be caused by completely different factors than
within group factors!
• Biased Tests
o Internal bias: the content of the test itself, will some groups do better than others
just by the items themselves?
i.e. language differences/cultural exposure to certain words/etc. o External bias: is it generalizable? Does it predict anything for people? AND does
it predict the same thing for diff groups?
o BUT, when we make tests as fair as possible, cultural differences mostly
diminish, but still somewh