there's a threshold that's 0.67 SDs (10 points) above the higher-performing of two groups with equal variances who are separated by 0.97 d.
With simulated group sizes of one million persons each, the mean differences decline, and the SDs do too. The new gap is 0.412 d.
But we know that the 0.97 d gap is an underestimate due to range restriction.
Using MBE scores, it looks like the unrestricted gap should be more like 1.22 d. That leaves us with a 0.537 d gap above the threshold.
Do we have subsequent performance measures?
Yes! We have three:
- Complaints made against attorneys
- Probations
- Disbarments
For men, the gaps, in order, are 0.576, 0.513, and 0.564 d. For women, the gaps are 0.576, 0.286, and 0.286 d.
Men fit expectations and women apparently needed less discipline.
These gaps probably replicate nationally.
For example, here are Texas pass rates from 2004 - a 0.961 d Black-White first-pass gap. The 2006 update to these figures raised the gap to 0.969 d.
Those figures are basically in line with LSAC's national study of Bar exam pass rates.
And those are basically in line with New York's gaps.
And this should probably be expected, since tests measure the same things.
Since all of the people included in these statistics went to ABA-accredited schools, they all had the opportunity to learn what was required to perform well on these tests.
But just like the Step examinations for medical doctors, the gaps on the tests and in real life remain.
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There's a popular belief that family wealth is gone in three generations.
The first earns it, the second stewards it, and the third spends it away: from shirtsleeves to shirtsleeves in three generations!
But how true is this belief?
Gregory Clark has new evidence🧵
The first thing to note is that family wealth is correlated across many generations. For example, in medieval England, this is how wealth at death correlates across six generations.
It correlates substantially enough to persist for twelve generations at observed rates of decay:
But why?
The dominant theory among laypeople is social: that the wealth is directly transmitted.
This is testable, and the Malthusian era provides us with lots of data for testing.
The Catholic Church helped to modernize the West due to its ban on cousin marriage and its disdain for adoption, but also by way of its opposition to polygyny.
The origin of this disdain arguably lies with Church Fathers like Justin Martyr, Irenaeus, and Tertullian🧵
Justin Martyr, in his Dialogue with Trypho argues with a Jew that Christians are the ones living in continuity with God's true intentions.
Justin sees Genesis 2 ("the two shall become one flesh") as normative.
In his apologetic world, Christians are supposed to transcend lust.
Irenaeus, in Against Heresies, is attacking Gnostics (Basilides, Carpocrates), whose sexual practices he finds scandalous.
To him, "temperance dwells, self-restraint is practiced, monogamy is observed"—polygyny is a doctrinal and moral deviation from creation affirmation.
The effects of charter schools on student test scores are meta-analytically estimated to be small.
In this study, the largest estimated effect was estimated to be equivalent to ~1.35 IQ points, for mathematics scores, which consistently showed larger effects than reading scores.
Similarly, the estimated effect of parents' preferred schools and of elite public secondary schools on test scores is around zero.
More interestingly, it seems charter school openings lead to competition that marginally boosts non-charter student performance and reduces absenteeism by very small degrees:
This analysis has several advantages compared to earlier ones.
The most obvious is the whole-genome data combined with a large sample size. All earlier whole-genome heritability estimates have been made using smaller samples, and thus had far greater uncertainty.
The next big thing is that the SNP and pedigree heritability estimates came from the same sample.
This can matter a lot.
If one sample has a heritability of 0.5 for a trait and another has a heritability of 0.4, it'd be a mistake to chalk the difference up to the method.