[gwern]

> That should be specific to a dark brown Chinese person; not to an African American.

If the preference were an idealized optimal algorithm, perhaps; but people are adaptation-executers. The simplest rule is 'lighter skin means richer', and so when one runs into an African, it's not necessarily perfect. (Although given how many poor African immigrants there are in China now, I'm not sure that's a bug rather than a feature.)