Consider Reardon, Kalogrides & Shores (2019). They found that even in districts where lower-performing groups had higher SES than Whites, they still tended to perform worse.
In this picture, 79% of the mean Black-White gap is independent of SES. At the metro level, 62% was.
It is a pernicious myth that test scores and achievement gaps are mere reflections of geography and that geography plays a major causal role in test scores.
The truth is that their association primarily reflects selection.
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 evidenceđź§µ
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 Tertullianđź§µ
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.