Anyway, Levitt summarizes:
His main finding: blacks who “sound black” earn salaries that are 10
percent lower than blacks who do not “sound black,” even after controlling for
measures of intelligence, experience in the work force, and other factors that
influence how much people earn. (For what it is worth, whites who “sound black”
earn 6 percent lower than other whites.)...It turns out you don’t want to sound
southern, either. Although pretty imprecisely estimated, it is almost as bad for
your wages to sound southern as it is to sound black, even controlling for
whether you live in the south.
Humans. Strange creatures. This is why I find economics interesting. Of course, regression analysis has its problems proving causation, but there are a lot of arrows pointing in the same direction in this research.
After being in academia for 14 years counting my time as a student, I have learned to dial back my rural Kentucky accent at least to a "mild" level if I feel the need. But, honestly, I kind of like "leaving it on" sometimes. And, I have to say in defense of accents, one of my most brilliant history professors had a heavy, gravelly, Mississippi drawl and another great prof had a classic Southern accent.
And, of course, there is a difference between speaking English well with an accent and speaking English poorly with an accent.