But if educational differentials and assortative mating lie behind much of the gap between those in Loudoun County and poorer Americans, they do not explain the Hamptons phenomenon.
The rate at which an epidemic spreads to lower-risk groups depends a great deal on whether different groups mate mainly among themselves (assortative mating) or whether they mate a lot with other people (disassortative mating).
Potentially, they may even reveal a form of the reverse assortative matching in that the top hospitals may be more likely to seek out MDs as leaders and vice versa.