Jewish IQ
108.5 for IQ, 109.8 to 111.5 for g.
The project talent dataset (nationally representative sample, large (~6900 Jews and ~140000 White gentiles with IQ data, many intelligence tests given) is the best dataset to test whether Jews are more intelligent than White gentiles. I previously reported that the difference in IQ between Jews and White gentiles within this data is roughly 6.7 points:
This estimate, unfortunately, was biased. Scores were adjusted for age, as biological maturation increases IQ, but there is the issue that some children are held back or accelerated, so some of the age association is not causal. Jews are younger at testing than White gentiles (Whites are 16.3, Jews are 15.8), because Whites and Jews advance through grades at different speeds. Notably, the individuals under 13 who were tested were notably more intelligent than the rest of the sample, despite their disadvantage in biological maturity. Because of this, adjusting for age (using a nonlinear spline) attenuates the advantage Jews have over Whites.
Conceptually, this bias can be adjusted for by taking the difference within age groups, which allows scores to be controlled for age, and it also avoids biasing the age control against Jews.
Difference in IQ after taking differences within age groups (no weights vs weighted by sample sizes within age groups):
Using the method of correlated vectors results in an estimate of 9.8-11.5 points, based on the difference that would be expected to be found in a subtest with a g-loading of 1.
Notes
This is what I was referring to before. I prefer to control for age using a spline, but in this case this underestimated the true intelligence of people who were advanced into older grades.
Proportion of people who are religiously Jewish by parent’s proficiency at speaking Yiddish (people who had missing data in the year 5 questionnaire were excluded):
MCV regressions:
Project Talent was the huge Sputnik Era test of American schoolkids (c. 1960), who were given two days of cognitive tests, right?
I'm married to a Jewish man but am not Jewish myself (except for a fraction of my DNA, courtesy of a Calabrian grandparent). I tested in the 99th percentile on an intelligence test as a kid, am a math whiz, and always felt pretty smart ... but oh man, my Jewish friends and husband are SO smart, insanely talented (the musical ability!!). My husband's memory and verbal IQ are way higher than mine (I'm better at math and logic and have better spatial skills). I don't even understand how he can remember the things he does. He'll pull obscure scientific jargon he's encountered once or twice out of nowhere. It's crazy.