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.
Phenotyping is the vast, minimally-explored frontier in genome-wide association studies.
Important threadđź§µ
Briefly, phenotyping is how you measure people's traits. Measure poorly, get bad results; measure well, get good results.
Example? Janky knees.
The janky knee example refers to osteoarthritis, the most common form of arthritis, which occurs when the cartilage between bones is worn down, so bones start rubbing against each other.
This ends up being very painful.
Everyone with this condition isn't necessarily diagnosed with it.
This is especially true for men, who tend to just ignore this (and many other conditions) more often than women do.
This is, in a word, annoying, because it means that if you study it, sampling is likely biased.