A little background on Obama`s maternal grandmother Madelyn`s family.
Madelyn Payne came from a respectable, relatively well-off family with some brainpower. Her sister Margaret is a now-retired professor of statistics living in Chapel Hill, N.C. Her brother Charley was an engineer for awhile, then attended graduate school at the U. of Chicago, where he ended up working for the rest of his career, becoming the assistant director of the massive UC library, and played a role in introducing computer technology to libraries. This U. of Chicago connection might have helped Madelyn`s daughter Ann get accepted at age 15 by the U. of Chicago, which used to take smart 15-year-olds frequently, such as geneticist James D. Watson, composer Philip Glass, and one of the Leopold & Loeb guys. (Ann eventually got her BA at the U. of Hawaii in math, then a Ph.D. in anthropology.)
Madelyn`s big mistake in life was falling in love with an unsuitable salesman from a dubious background named Stan Dunham, much to her parents` regret. Madelyn paid for her rebellion with a lifetime of hard work. She didn`t particularly want to be a feminist role model (her ambitions were more to be a genteel housewife with time for volunteer work and bridge), but her erratic husband didn`t leave her much choice except to be one of the first women to climb the career ladder to executive rank in Honolulu`s banking industry.
So, the Paynes were a family with a fair amount of analytical ability.