这样的例子很多。尤其在经济管理和数学统计等方向。
举个列子：
http://web.mit.edu/newsoffice/2001/summers.html
Lawrence H. Summers
He received his bachelor's degree in economics at MIT in 1975 and his PhD at Harvard in 1982. He served three years on the MIT economics faculty, where he was named assistant professor in 1979 and associate professor in 1982.