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Some of you may have noticed how little I've tweeted over the past two months. There's a reason for this.

I became aware back in April that a "freelance writer" was planning on doing an "expose" on me that would disclose my identity and professional affiliations. For what it's worth, I don't think this person actually is a freelance writer, but rather someone who threatens and attacks and publicly discloses the identity of people who are interested in intelligence research.

Since this is being discussed on X today:

"Ashkenazi Jews have the highest average IQ of any ethnic group for which there are reliable data. They score 0.75 to 1.0 standard deviations above the general European average, corresponding to an IQ 112 – 115."

slatestarcodex.com/2017/05/26/the… "Ashkenazi Jews are just as successful as their tested IQ would predict, and they are hugely overrepresented in occupations and fields with the highest cognitive demands."

Study finds male-female brain differences and is able to predict "individual IQ scores for males and females separately using whole-brain functional connectivity."

academic.oup.com/cercor/article… "Robust predictions of intellectual capabilities were achieved across three independent data sets (680 subjects) and two intelligence measurements (IQ and fluid intelligence) using the same model within each gender."

@kareem_carr (Thread Response)

(1)

Some of the assertions made in your thread are outside the scientific mainstream.

Let's begin with your claim that IQ is not an “objective measure of intelligence”... @kareem_carr (2)

IQ is the most robust major effect in all of psychology, endlessly replicable and with effect sizes unheard in the discipline, up to and beyond 0.90. Its predictive validity across dozens of outcomes is supported in 1000s of published peer-reviewed studies.

I'm suspending my normal prohibition against tweeting links outside published scientific literature to link you to this excellent blog post from psychologist Russell Warne.

I condense his conclusions below.

russellwarne.com/2023/04/29/stu… "Although it does not take much education for humans to start classifying objects abstractly, many people in the world do not have that level of education, or the education is very low quality."

"Ashkenazi Jews have the highest average IQ of any ethnic group for which there are reliable data. They score 0.75 to 1.0 standard deviations above the general European average, corresponding to an IQ 112 – 115."

slatestarcodex.com/2017/05/26/the… "This fact has social significance because IQ (as measured by IQ tests) is the best predictor we have of success in academic subjects and most jobs."

(Thread)

Pervasive myths about human intelligence include:

— Genes are not important for determining intelligence

— IQ tests only measure how good you are at taking tests

— Racial IQ differences are completely environmental

— IQ does not correspond to brain anatomy — Multiple intelligences exist

— Noncognitive variables have powerful effects on academic achievement

— Stereotype threat explains score gaps

— IQ only reflects a person's socioeconomic status

— Intelligence tests are biased against diverse populations

The controversial national IQ dataset of Richard Lynn and David Becker (especially controversial for its IQ estimates of African nations) is thoroughly analyzed for the first time in this just-published paper.

link.springer.com/article/10.100… From the abstract: "My hope is that the scientific community can chart a middle course and reject the false dichotomy of either accepting the scores without reservation or rejecting the entire dataset out of hand."

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 25: Rebutting the Environmentalist Claim That Income Disparities Between Blacks and Whites Explain the IQ Gap Environmentalists believe average differences between races in exposure to certain variables like poverty, nutrition, education, parenting, and health care explain the race IQ gaps.

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 24: Shared and Non-Shared Environmental Variables So, if environmentalists don't believe genetic differences between races influence the IQ gaps between them, what do they think causes them?

They attribute the gaps to environmental factors like nutrition, education, poverty, and health care.

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 23: Rebutting the Environmentalist Claim of Stereotype Threat One of the most popular environmentalist arguments in the race and IQ debate has been stereotype threat.

This theory posits that blacks aren't less smart on average, they just perform worse on IQ tests because they're conforming to existing stereotypes about them.

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 22: Cultural Fairness of IQ Tests Some people have argued that the “cultural specificity” of intelligence makes IQ tests biased towards the environments in which they were designed, and therefore a particular test developed for a “white” culture may not accurately measure intelligence in a non-white one.

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 21: Rebutting Claims That IQ Tests Don't Measure Intelligence (Or Anything Valuable) One type of rebuttal sometimes appearing in the popular media, but almost never made by scientists, can be expressed as “intelligence cannot be measured,” and also, relatedly, “IQ tests don't measure anything but one's ability to take IQ tests.”

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 20: Rebutting the Environmentalists Regarding the Flynn Effect, and James Flynn on Free Scientific Inquiry A leading argument that has been used (more in the past than presently) against a hereditarian explanation for race IQ gaps relies upon the so-called “Flynn Effect,” named after the recently-deceased intelligence researcher James Flynn.

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 19: Rebutting the Environmentalist Claim That '50,000-150,000 Years Is Not Enough Time For Brain Differences To Evolve Between Groups' Some scientists claim that there hasn't been enough time for meaningful evolutionary changes to take place in the human brain in the 50,000 to 150,000 years since humans left Africa — changes that might have caused differences in IQ between geographically-separated groups.

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 18: Rebutting the Environmentalist Claim That 'Race Is Purely a Social Construct' In the last several threads, I've described the hereditarian explanation for racial differences in IQ.

Let's turn now to the rebuttal points made by those favoring an environmental hypothesis for the race IQ gaps.

I'll then rebut those rebuttals.

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 17: The Hereditarian Explanation — Summary In summary, even apart from GWAS/PGS, a compelling case for a genetic explanation for race IQ gaps can be made from the overwhelming evidence for the role of genes in IQ differences between individuals, the consistent large gaps in IQ and academic testing performance,...

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 16: The Hereditarian Explanation — GWAS/PGS and Group Differences This might be a good time to revisit GWAS, an advance in genomics which has identified the *specific* genetic variants associated with IQ and then had these variants' IQ-predictive values quantified by polygenic risk scoring (PGS or PRS).

Background:

https://twitter.com/PaoloShirasi/status/1551576350602960896

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 15: The Hereditarian Explanation — Individual and Group Differences A quick reminder thread to stress that while INDIVIDUAL differences in intelligence are due overwhelmingly to heritability/genes this does not necessarily mean that GROUP differences (like those between the races) are primarily genetically-influenced.

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 14: The Hereditarian Explanation –- Miscellaneous Findings Over the last few previous threads, I've discussed some of the more well-known scientific findings and areas of research cited by hereditarians to argue for a genetic basis for racial differences in IQ. Now I'll very briefly discuss some less well-known ones.

[THREAD]

A VERY BASIC INTRODUCTION TO THE HEREDITARIAN POSITION ON RACE AND IQ.

PART 13: The Hereditarian Explanation –- Admixture Studies So far I've talked about how the overwhelmingly genetic basis of individual differences in IQ, along with findings from transracial adoption studies, brain studies and population genetics, tend to support a hereditarian (genetic) explanation for the IQ gaps between races.