A quadratic equation divided by a Integral. I guess it would depend on the type of doctorate, and the school offering the program. Probably smarter than the average bear, but not brilliant. They probably should be known more for their intestinal fortitude to spend most of their life in school. And now that preschooling starts even before birth, they have been in a life of being taught academia, while only glimpsing of life.
My point is the IQ needs to be entwined with RQ, real life.