This article from Forbes asks the question "do Harvard grads run companies better?"
Harvard Business School prides itself on graduates who go on to become successful leaders of America's top companies. There are currently 57 Forbes 500s chief executives who earned their M.B.A. degrees from Harvard, the most of any business school. Both Wharton and Stanford come in at a far second, each with only 15 chiefs represented.
Stock price is used as a measure of managerial success, which I would dispute as too simplistic. Even if Harvard grads are more successful, the question arises, "does Harvard turn out better educated students, or do better students simply choose Harvard?" I lean towards the latter.