No mention of genes in it, but seems like genetic selection for intelligence. The media were hyping it as evidence gay parents are better. I think it's more like lesbian couples get to pick a sperm donor and choose wisely. I think if gay couples were to always use surrogates and pick intelligent and stable sperm/egg donors, they'd be quite eugenic. Note the small number of gay male couples with kids though (although the paper does highlight some additional reasons for why this is, I suspect most gay men have no interest in kids, kind of makes me think the whole moral panic about gay men and kids is a bit overblown...)
Anyway this study could be worth discussing at some point. The sociology journal isn't going to get into how genes might influence outcomes, naturally.
It gives me an idea: it would be incredibly interesting to check the correlation between "half-siblings reared apart" who were both the result of using the same sperm donor for different lesbian couples. This might become a possibility in the future.
Here's another interesting paper. It has long been thought that pedophiles have higher rates of left handedness, consistent with atypical lateralisation of the brain. A new analysis suggests this is false: https://osf.io/preprints/psyarxiv/4vtd8/
"Within 114 African regions with mathematics test and age heaping results, the correlations ranged between 0.40 and 0.71" this should be r^2, so that the correlation would roughly be 0.636(0.846 with country fixed effects), between age heaping of those age 40-50 and children's mathematics tests across regions in 12 african countries(see https://unesdoc.unesco.org/ark:/48223/pf0000380095 for more info and an age heaping map for all available countries/regions). Also might be worth mentioning beta regression when it comes to ceiling effects for the age heaping(requires data for multiple years, including those further away from the threshold for the groups in question), which has been used in a couple of papers(the francis and kirkegaard one which had a 0.7 correlation between late 19th century-early 20th century age heaping and modern iqs, and the italian study by kirkegaard and piffer).
"Since this analysis requires enormous samples to be well-powered, it cannot be attempted without much larger samples than are presently available for many traits."
Depends a great deal on the variation in admixture within the population and the difference between the two groups, with gwern only assuming a sd of 1%(so 4% within the african american population and a standard deviation for siblings in IBD of 4%), and a gap size of 9 points between black and white americans. With more reasonable estimates for the mean and variation of admixture within the african american population(gwern found 11% within the general population, and later meta-analysis found basically the same result(https://rpubs.com/JLLJ/BGH)), and a typical 1.1d/g gap, you would only need a few thousand siblings for 80% power. I used the results from the ABCD sample(Hu,2022 , table 2) and resued the code in r(including mixed race adolescents, for a signifcantly higher variation in admixture), and with N=1000 there was just under 80% power. This sample size in within reach in the near future(add health has over 20,000 adolescents, although when looking at african americans siblings with cognitive data, that might not be enough).
Also there was no correlation between skin colour and IQ within siblings in the NLSY 97 sample(https://www.mdpi.com/2624-8611/1/1/17,expected because of the few genes controlling skin/hair/eye colour vs high polygenicity of g), and thus colourism is not a problem for this analysis(also a point against colourism, which was pointed out for social outcomes in your article). Still worth replication in the NLSY79 and CLNSY.
"They observed all the typical findings: a 1.10 Hedge’s g gap in intelligence between Blacks and Whites; Whites were 98% European and Blacks were 72% African; and admixture mediated 75.68% of the difference in intelligence between Blacks and Whites, as indicated by the 0.18 correlation within the Black group."
Might be worth pointing out that when black immigrants were excluded(and probably a specific definition of black american, so excluding those who identified as black and another SIRE group), almost 100% was mediated with MCGFA(with means of 98% and 17% and a standard deviation of 10%, there is a difference of admixture of 8.1 sd, and thus with a correlation of 0.13 within
Do you know why there's a slightly higher(black-white) gap using EFA compared to MCGFA in this sample? Is it just influence from group factors that differ beyond g.
Cremieux, had to post this here because I didn't know if you'd be notified of my comment on Aporia magazine.
This large Dutch study found that children of same-sex couples performed better in school tests: https://journals.sagepub.com/doi/full/10.1177/0003122420957249
No mention of genes in it, but seems like genetic selection for intelligence. The media were hyping it as evidence gay parents are better. I think it's more like lesbian couples get to pick a sperm donor and choose wisely. I think if gay couples were to always use surrogates and pick intelligent and stable sperm/egg donors, they'd be quite eugenic. Note the small number of gay male couples with kids though (although the paper does highlight some additional reasons for why this is, I suspect most gay men have no interest in kids, kind of makes me think the whole moral panic about gay men and kids is a bit overblown...)
Anyway this study could be worth discussing at some point. The sociology journal isn't going to get into how genes might influence outcomes, naturally.
Thanks for sending me this.
It gives me an idea: it would be incredibly interesting to check the correlation between "half-siblings reared apart" who were both the result of using the same sperm donor for different lesbian couples. This might become a possibility in the future.
Here's another interesting paper. It has long been thought that pedophiles have higher rates of left handedness, consistent with atypical lateralisation of the brain. A new analysis suggests this is false: https://osf.io/preprints/psyarxiv/4vtd8/
"Within 114 African regions with mathematics test and age heaping results, the correlations ranged between 0.40 and 0.71" this should be r^2, so that the correlation would roughly be 0.636(0.846 with country fixed effects), between age heaping of those age 40-50 and children's mathematics tests across regions in 12 african countries(see https://unesdoc.unesco.org/ark:/48223/pf0000380095 for more info and an age heaping map for all available countries/regions). Also might be worth mentioning beta regression when it comes to ceiling effects for the age heaping(requires data for multiple years, including those further away from the threshold for the groups in question), which has been used in a couple of papers(the francis and kirkegaard one which had a 0.7 correlation between late 19th century-early 20th century age heaping and modern iqs, and the italian study by kirkegaard and piffer).
"Since this analysis requires enormous samples to be well-powered, it cannot be attempted without much larger samples than are presently available for many traits."
Depends a great deal on the variation in admixture within the population and the difference between the two groups, with gwern only assuming a sd of 1%(so 4% within the african american population and a standard deviation for siblings in IBD of 4%), and a gap size of 9 points between black and white americans. With more reasonable estimates for the mean and variation of admixture within the african american population(gwern found 11% within the general population, and later meta-analysis found basically the same result(https://rpubs.com/JLLJ/BGH)), and a typical 1.1d/g gap, you would only need a few thousand siblings for 80% power. I used the results from the ABCD sample(Hu,2022 , table 2) and resued the code in r(including mixed race adolescents, for a signifcantly higher variation in admixture), and with N=1000 there was just under 80% power. This sample size in within reach in the near future(add health has over 20,000 adolescents, although when looking at african americans siblings with cognitive data, that might not be enough).
Also there was no correlation between skin colour and IQ within siblings in the NLSY 97 sample(https://www.mdpi.com/2624-8611/1/1/17,expected because of the few genes controlling skin/hair/eye colour vs high polygenicity of g), and thus colourism is not a problem for this analysis(also a point against colourism, which was pointed out for social outcomes in your article). Still worth replication in the NLSY79 and CLNSY.
"They observed all the typical findings: a 1.10 Hedge’s g gap in intelligence between Blacks and Whites; Whites were 98% European and Blacks were 72% African; and admixture mediated 75.68% of the difference in intelligence between Blacks and Whites, as indicated by the 0.18 correlation within the Black group."
Might be worth pointing out that when black immigrants were excluded(and probably a specific definition of black american, so excluding those who identified as black and another SIRE group), almost 100% was mediated with MCGFA(with means of 98% and 17% and a standard deviation of 10%, there is a difference of admixture of 8.1 sd, and thus with a correlation of 0.13 within
non-immigrant black americans, a 1.053 d gap can be explained by admixture, compared to a 1d/1.08g gap in this sample). Source:(https://www.researchgate.net/publication/354766954_Genetic_ancestry_and_general_cognitive_ability_supplpdf).
That's a wonderful find! Thanks for bringing it to my attention.
Do you know why there's a slightly higher(black-white) gap using EFA compared to MCGFA in this sample? Is it just influence from group factors that differ beyond g.
I don't know. You could ping the original authors to see what they say. I'd be interested, so if you did that, make sure to report back!
Cremieux, I strongly suggest you get on the network:
https://eharding.substack.com/p/why-does-russian-physical-therapy
"In a particularly revealing case, Alexander Luria recorded that illiterate Uzbeks could not complete syllogisms"
The real mystery is whether literate Uzbeks can complete syllogisms:
https://manifold.markets/EnopoletusHarding/will-luria-replicate
This is an amazing article. I wish I had the patience to read it.😆
Sent myself a link. I’ll have another crack at it
Checking age heaping as a measure of numeracy is brilliant but limited. But it was worth the read for that alone.
Not sure about the IQ part.