1. Historical misuses and contemporary issues
Race and IQ
Historical misuses and contemporary issues

2. Race and IQ The history of IQ testing A brief introduction to IQ tests
Race-group differences
A summary of the issue
Possible explanations
Test bias
Genetic differences
Environmental differences

3. A long (and mostly sordid) history

4. Craniometry (1860) Pierre Brocca Believed brain size=intelligence
Interesting methods…
Concluded:
“The brain is larger in mature adults than in the elderly, in men than women,…in superior races than in inferior races”
(Brocca quoted by Gould, 1978, p. 44)

5. Alfred Binet
Lawyer, self taught in psychology, studied under Charcot (who also influenced Freud)
Asked by French government to create a test to identify students who would benefit from remedial education
Along with Theodore Simon, created first widely-used standardized test of intelligence, the Simon-Binet Scale

6. The birth of the IQ test
France legislates mandatory primary education in 1882
Government requests test to identify students who need “special ed.”
Alfred Binet publishes (with Theodore Simon) the first widely-used standardized IQ test (with 30 subtests) the Simon-Binet Scale (1905)
Digit repetition
Sentence completion
Point to an object in a picture
Conscious recognition of resemblances
How are a fly, an ant, a butterfly, a flea alike?
In what way are a newspaper, a label, a picture alike?
Recognition of food
Moral judgment
Revised scale published in 1908
14 tests retained, 9 dropped, 7 modified, 33 added
If 75-90% of children in age group pass, it was assigned that age level
Rejected notion of “IQ”

7. Henry Goddard Translated Simon-Binet into English (1908)
Distributed 22,000 copies of translated test across the U.S.
Set up first laboratory to study mental retardation in New Jersey:      Vineland Training School for Feebleminded Girls & Boys 
Strong advocate of eugenics
1912 book The Kallikak Family: A Study in the Heredity of Feeble-mindedness
original article
summary and analysis

8. Goddard (continued)
Wanted to prevent the breeding of feebleminded people
hesitated to promote compulsory sterilization, even though convinced it would solve problem
suggested "colonies" where the feeble-minded could be segregated
Established an intelligence testing program on Ellis Island in 1913
rejects 80% of “pre-identified” immigrants as "feeble-minded"
83% of all Jews
80% of the Hungarians
79% of the Italians
87% of the Russians.
resulted in an exponential increase in deportations

9. Goddard (continued) The Immigration Restriction Act (1924-1965)
Strongly influenced by American eugenics' efforts restricted numbers of immigrants from undesirable racial groups (including Jews). 
Upon signing, President Coolidge commented, "America must remain American." 
Publicized race-group differences on Army IQ tests and claimed Americans were unfit for Democracy
One of many scientists (including Galton and Terman) that inspired scientific racism movement in Europe & U.S.

10. Robert Yerkes Founded first non-human primate research lab
Chaired committee that created the Army Alpha and Beta intelligence tests used in U.S. during World War I
Sample items

11. David Wechsler Born in Rumania, emigrated to U.S. at age 6
Worked as a psychological examiner in army during WWI
Obtained Ph.D. in 1925
Chief psychologist at Bellevue Psychiatric Hospital from
Developed several intelligence tests, including Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Intelligence Scale for Children (WISC).

12. WAIS Popularity
WAIS

13. Defining Intelligence
“Global capacity to act purposefully, to think rationally, and to deal effectively with the environment” (David Wechsler)
1987 survey of 1020 experts on intelligence
Abstract reasoning (99.3%)
Problem-solving ability (97.7%)
Capacity to acquire knowledge (96.0%)
Memory (80.5%)
Adaptation to environment (77.2%)

14. Intelligence vs other types of tests
Aptitude tests measure a narrow range of ability
Achievement tests measure what you know or what you learned/achieved
Question: What is the SAT?
Answer: A multiple aptitude test (related to intelligence)

15. SAT to IQ conversion table
V+M IQ
15 SD
%ile
1600
152.18
99.975
1010
109.46
73.587
1590
151.45
99.970
1000
108.74
71.985
1580
150.73
99.964
990
108.01
70.338
1570
150.00
99.957
980
107.29
68.647
1560
149.28
99.949
970
106.56
66.916
1550
148.56
99.940
960
105.84
65.149
1540
147.83
99.929
950
105.12
63.347
1530
147.11
99.916
940
104.39
61.516
1520
146.38
99.901
930
103.67
59.659
1510
145.66
99.883
920
102.94
57.780
1500
144.94
99.863
910
102.22
55.883
1490
144.21
99.840
900
101.50
53.972
1480
143.49
99.813
890
100.77
52.052
1470
142.76
99.782
880
100.05
50.128

16. Relationship between SAT and IQ
1. For SAT scores before 1996
IQ = (0.126 x SAT combined) + (-.4.71E - 5 x SAT combined x SAT combined) (Detterman and Frey, Case Western Reserve Univ.)
2. For SAT scores from
IQ =(0.095 X SAT Math) + (0.003 X SAT Verbal) Scores for SAT were "re-centered" in 1996, raising the average SAT back to 500 (Detterman and Frey, Case Western Reserve Univ.)
“SAT to IQ conversion is an inexact science, particularly for SAT's under 900. The chart's creator writes: "The lowest point of reference was the theoretical average IQ of high school students being 110 and the current average SAT I V+M (verbal + math) score being Everything below that is extrapolation. Also note that the decimal places give the impression that the numbers are more precise than they really are."

17. WAIS Verbal Subtests

18. WAIS Performance Subtests
Picture Completion
Picture Arrangement
Block Design
Object Assembly
Digit-Symbol Substitution

19. Interpreting IQ scores

20. Interpreting IQ scores (normal curve)

21. The Flynn Effect (1995 data)
IQ scores tend to rise 3 points every 10 years

22. Does IQ matter? How can we tell? Data indicate
IQ and school performance (GPA)
r=.50 for elementary and high school students
r=.40 for college students
IQ and years of education (r=.50, see next slide)
IQ and occupational attainment (r=.50)
Likely due to very high correlation (r= mid .60s) between education and occupation
IQ and job performance (rs= .27 to .47)

23. IQ and Education

24. IQ and education/occupation (same data)

25. IQ tests’ strengths and weaknesses

26. The IQ racial gap

27. Possible explanations for the gap
The tests are bad
Genetic differences
Environmental differences

28. Are the tests (racially) biased?
Argument 1: IQ tests yield race-group differences, hence
the tests are biased
Argument 2: The test item content is culturally biased
Example: “What should you do when a child smaller than you begins to fight with you?” (comprehension)

29. Chitling Intelligence Test (Dove, 1971)
A "handkerchief head" is:
   (a) a cool cat
(b) a porter
(c) an Uncle Tom
(d) a hoddi
(e) a preacher
Many people say that "Juneteenth" (June 19) should be made a legal holiday because this was the day when:
(a) the slaves were freed in the USA
(b) the slaves were freed in Texas
(c) the slaves were freed in Jamaica
(d) the  slaves were freed in California
(e) Martin Luther King was born
(f) Booker T. Washington died. CB

30. Black Intelligence Test of Cultural Homogeneity
100-item multiple-choice test, based on items drawn from Black culture
Sample Questions
1. Alley Apple is
a) brick b) piece of fruit c) dog d) horse
2. CPT means a standard of
a) time b) tune c) tale d) twist
3. Deuce-and-a-quarter is
a) money b) a car c) a house d) dice
A, A, B

31. Are the culture-specific tests valid?
Useful for building self-esteem
But low predictive validity
Low correlation between “Black” IQ Test and achievement (Language =. 33, Math=.18)
Students in MR classes did no better on the “Black” IQ Test than on the WISC

32. Cultural bias data

33. Are the tests (racially) biased?
Argument 3:
The tests have different construct validity for Blacks and Whites

34. Are the tests (racially) biased?
Argument 4:
The tests have different/inadequate predictive validity for Blacks and Whites
B.I.T.C.H. correlations:
Language =. 33
Math=.18

35. IQ and Education (1990)

36. Are the tests (racially) biased?
Argument 5:
The tests have language bias because they are in standard English and many Blacks grow up speaking a Black dialect

37. Are the tests (racially) biased?
Argument 6:
The tests are neutral but the examiners are biased
Evidence:
25 of 29 studies published prior to 1995 found no significant relationship between the race of the examiner and Black children’s scores

38. Are the tests (racially) biased?
Argument 7:
The tests are neutral but the norms are inappropriate
In other words: Separate (rather than national) norms should be used to eliminate racial bias [recent example]
Logical outcome (if taken to logical conclusion):
Race group differences would be eliminated, but…
Scores would have little relevance to racial justice, and
Scores would not allow tracking of group outcomes/disparities

39. Possible explanations for the gap
The tests are bad (no empirical support for current racial bias!)
Genetic differences
Environmental differences

40. The heritability of IQ

41. Historical and current understanding
Heritability debate has a long, controversial history
In the 1960's Arthur Jensen fueled debate with heritability estimate of .8
The Bell Curve (1994) by Herrnstein and Murray
Contemporary consensus
Evidence does exist for high heritability, but
Environmental factors are also important
Studies show heritability = .4 to .8 (best estimate probably .7)
High heritability does not discount environmental influence. Consider vocabulary
So are psychological factors (e.g., Carol Dweck’s work)

42. The genetic position A. Assumptions
1. IQ is polygenetic (Gottesman’s model postulates 5 genes)
2. IQ is normally distributed
3. Very low IQ is produced by genetic abnormalities
B. Evidence
1. Average IQ correlation of identical twins is .86
2. Identical twins, fraternal twins, siblings, and parent-child IQ correlations all higher than that of unrelated persons
3. Parent-child correlations are higher for biological vs adopted parents
4. When siblings are reared together, IQ correlations are higher for biological siblings than for adopted siblings
5. The high correlation in #1 resists change over time
6. Many genetic abnormalities have been proven to cause lower IQ
a. Turner’s syndrome
b. Fragile X syndrome
c. PKU

43. The environmentalist position
A. Assumptions
1. Genetics alone cannot account for the normal range of IQ
2. IQ is not necessarily normally distributed (tests are designed to yield a normal distribution)
B. Evidence
1. IQ corrs of identical and fraternal twins raised together are higher than
for those raised apart.
2. Fraternal twins IQ correlations are higher than siblings’s IQ correlations
3. Assortative mating
4. Adoptive parent-child correlations are higher than unrelated adults and children
5. Studies of environmental influences on IQ show that
a. Low birth weight decreases IQ
b. Malnutrition decreases IQ
c. Family background affects IQ
d. Pressure to achieve increases IQ
e. Birth order and family size affect IQ
f. Amount and quality of schooling affects IQ

44. But is the racial gap genetic?
Hard to determine due to environmental differences.

45. Is the racial gap genetic?
Many controversial “studies”

46. Between-group vs within-group variation

47. What we know about IQ heritability
There is strong evidence of within-group heritability
Laws of heredity produce regression to the mean
There is a certain environment by gene interaction

48. What we know about IQ heritability (cont.)
1987 survey of 1020 intelligence experts
The difference is entirely due to environmental variation: 15%.
The difference is entirely due to genetic variation: 1%
The difference is a product of genetic and environmental variation: 45%.
The data are insufficient to support any reasonable opinion: 24%.
No response (or not qualified): 14%.
Robert Sternberg: "science isn't done by majority rule"
APA 1997 task force: “It is sometimes suggested that the Black/White differential in psychometric intelligence is partly due to genetic differences. There is not much direct evidence on this point, but what little there is fails to support the genetic hypothesis.”
Charles Murray: “Actually, there is no direct evidence at all, just a wide variety of indirect evidence, almost all of which the task force chose to ignore.”

49. David Reich NY Times Editorial: How Genetics is Changing Our Understanding of Race
If scientists don’t say what evidence is regarding genetics/biology and race, then racists will fill the gap and void with hateful untruthful nonsense.
Thus scientists have a duty/obligation to inform public on current findings/evidence on genetics/biology and race.
Arguable point—would racists really stop because scientists aren’t communicating?
Reactions:
NY Times piece then served as launching point for reigniting various camps to restate their opinions and positions.
Many publications, blogs reacting and re-reacting; mostly around race, genetics, and IQ. Mostly people re-arguing their long-held positions and using NY Times piece as opportunity to have same discussions and debates (e.g., Sam Harris, Charles Murray, Nicholas Wade).

50. Nicholas Wade: NY Times response
“At last! A Harvard geneticist, David Reich, admits that there are genetic differences between human races, even though he puts the word race in quotation marks.
Obvious as this may seem, American academics for decades have insisted that race is a social construct, and have vilified as a racist anyone who says otherwise.
After covering the human genome project for this newspaper for many years, I wrote a book, “A Troublesome Inheritance,” which explained that there is indeed a biological basis to race, a fact that Mr. Reich has now echoed, though without acknowledgment.
He even tries to portray my book as racist, which it is not.
Acknowledging that race has a biological basis is a salutary advance. Opposition to racism should rest not on the lie that races don’t exist but on principle, allowing science to proceed without hindrance.”

51. Genetics, race, and intelligence: The evidence and the arguments
There are group differences (race; can also be other groups—sex, sexual preferences) in the outcome means (IQ as WAIS; SAT; education attainment; other constructs)
Heritability of outcome is non-zero. Higher heritability stronger people believe.
Most agree that both A and B are true.
Argument: is A because of B?
NO. logically not true.
Also helps to have understanding of genetics and race definition to further challenge view. Same basis of Charles Murray The Bell Curve

52. Quick primer on genetics: Why it matters
Plomin Nature Review Genetics 2018: “GPSs are unique predictors in the behavioural sciences. They are an exception to the rule that correlations do not imply causation in the sense that there can be no backward causation when GPSs are correlated with traits.”
When people say and write this, including genetics experts, what are we to think? What implications and inferences can be made on such assertions? Are they even true? What is causal in genetics? (e.g., Turkeimer responses)
What is said about Point B?
1. Intelligence is highly heritable, with mean estimates around 80%.
2. New big GWAS studies are finding specific alleles and explaining molecular genetic basis of intelligence.
Careful examination of these points:
What you need to know? Causality and genetics?
Behavior genetics: Heritability as statistic
Molecular genetics: SNPs and GWAS

53. Basic BG Design
Identical twins (MZ) share 100% genes; fraternal twins (DZ) share 50% genes on average.
Major “parts” to twin BG study:
Additive genes (A), helps calculate “heritability.”
Heritability is just a statistic. A number ranging from 0-1.0
Environment: 2 parts
Common Environment (C)
Unique Environment (and error) (E)
Phenotypic variance (any measured trait) = Additive genes (A) + Common Environment (C) + Unique Environment (E)

54. A,C,E model in behavior genetics
Remember, heritability is a number, from a stat formula. Will change depending on specific study, sample, methods, etc.
No one, specific “heritability index” for any phenotype

55. Intelligence and IQ are mostly heritable and genetic, right
Intelligence and IQ are mostly heritable and genetic, right? People are born smart and stay that way over their life, right? Development and context in genetics

56. Development matters: IQ example of Heritability, environment

57. Context also matters! IQ example: SES, genes, environment
7 year old kids
Environment: ~60% in low SES
Genetics:
>60% in high SES
Turkheimer et al 2003 Psych Science

58. BG Heritability: Summary
Heritability of IQ/intelligence. Overall heritability ranges 58-86% in adults (Plomin 2018).
REMEMBER: % heritability (e.g., in IQ/intelligence) is not a static, “real” number or amount of how much any construct is absolutely “explained by” genetics.
There are gene-environment interplay effects: rGE and GxE. Often these go into A portion of heritability in BG statistics, yet this nature-nurture interplay involves environment and not “pure genetics.”
Developmental and context effects: heritability increases with age. Heritability, as statistic, changes dependent on environment, sample, context.

59. Molecular genetics: SNPs and GWAS
Examine thousands of SNPs, each of tiny effect size. SNPs can be anywhere on genome, often in noncoding regions
Intelligence, many psych constructs, are highly polygenic. Small effects.
Aggregate all of these small SNP effects into Genomewide Polygenic Score (PGS)– a composite of SNP associations, weighted by correlation with the trait
Then each individual can receive PGS, used in stat analysis
There are molecular genetic associations in many outcomes (e.g. medical) that can vary by self-identified racial group

60. Are genetic effects causal? For what?
Genetics is not deterministic or immutable, in most cases, especially in psychology
Most medical and psychological outcomes are highly polygenic, of small effect, and affected by environment.
Examples:
the EA2 GPS predicts twice as much variance in educational attainment and occupational status in the post-Soviet era as in the Soviet era in Estonia. Finding interpreted as the hypothesis that heritability is an index of equality of opportunity and meritocracy
IQ is highly heritable. Compulsory education has improved average intelligence and achievement in many countries
Height is highly heritable. Average height has increased considerably over decades—better diet

61. Definitions and concepts of race
Different scientific disciplines’ definitions and concepts of race. E.g., anthropology
Genetics: self-reported race statistically correlated with ancestry, not perfectly
Self-identified Black in U.S.—80% (average) of genome derived from enslaved Africans
White in U.S.—unspecified admixture of different pops.

62. Definitions of race
Reich in NY Times uses “race” and “black” in quotes.
Helpful? Useful?
Distinguish concepts of races from populations or groups?
His motivation?
To illustrate lack of precision of race in genetic definitional terms?
At start, acknowledges race is social construct.
Trying to be careful and triangulate and thread needle between these different camps?
Still…racists already using this piece to support their positions.
Reich’s main point: do not “leave vacuum that gets filled by pseudoscience.”

63. Averages/groups vs individuals
Average difference between ancestral populations/races are very small compared to variation within populations (individual differences).
Remember always much bigger individual differences than group differences (same in gender differences) for most any psych/social construct (eg., IQ, depression, personality).
Can show normal distributions of massive overlap with most variance in individual differences, can be tiny between groups effect.
Turkheimer and thought experiments: Focus on mechanism. Once known, no need to appeal to averages at group level.

64. DISCUSSION

65. Population stratification classic example
Relationship between the presence of the Gm3;5,13,14 haplotype and type 2 diabetes mellitus among residents of a Pima–Papago Indian reservation with varying degrees of European ancestry. With restriction to those who are 35 years of age or older and with 0 or eight Indian great grandparents, the estimate of the odds ratio between haplotype status and diabetes is 0.35 without accounting for Indian heritage; on adjustment for Indian heritage, the estimate of the odds ratio rises to much weaker evidence risk of diabetes.

66. Questions
With these points (e.g. groups vs individuals; lack of mechanism knowledge; unclear definitions and loose terminology)…
does the study of differences between ancestral groups/races on behavioral/cognitive/psychological construct (eg, intelligence) automatically make the scholar a racist?
Is there a place for for abstract, pure, theoretical scholarly inquiry into groups (race, gender, sexuality, etc) and biology/gender that can be absent of obvious implications and inferences to be made in current society?
Are there ways to write about likely eventual paper saying there may be genetic associations (small?) mediating racial group effects in intelligence—ways to “innoculate” against racists taking such findings as evidence for typical faulty interpretations of such data.?

67. Possible explanations for the gap
The tests are bad (no empirical support)
Genetic differences (data mixed, no consensus)
Environmental differences

68. Environmental Factors
Social class and home environment matter
Attribution of intelligence matters (Dweck)
Motivation and test taking stills matters
Stereotype threat matters
Interventions matter

69. Scores have narrowed in past 30 years

70. Social Class matters
Bell curve, 1994

71. Family Factors and IQ
R2=.0576

72. Home environments

73. Environmental Factors
Social class and home environment matter
Attribution of intelligence matters (Dweck)
Motivation and test taking stills matters
Stereotype threat matters
Interventions matter

74. Stereotype threat matters
Stereotype threat literature
Steele and Aronson (1995)
Ryan and Anthony (2006)

75. Interventions matter
Recent NY Times article: Who gets to graduate?

76. The Culture of Poverty (Kutner, 1975)

77. Blaming the victim (Ryan, 1976)
Four Steps to Blaming the Victim
Identify a social problem
Study those affected by the problem to discover how they are different from those who are not affected by the problem.
Define the difference as the cause of the problem itself
Create a humanitarian action (social service) program to correct the problem cause (from #3)
Real-world example:

78. Blaming the (IQ) victim
1. Social problem:
African American children underperforming (relative to Whites) on IQ tests
2. Study those affected by the problem to discover how they are different from those who are not affected by the problem
Black families more likely to be less educated
Black families more likely to have poor study spaces
Black children more likely to be unmotivated to do well on tests
Black children less likely to associate education with success

79. Blaming the (IQ) victim, continued
3. Define the difference as the cause of the problem itself
Black children under-perform on IQ tests because Black families don’t value education
4. Create a humanitarian action (social service) program to correct the problem cause ?