Noted: Most studies have focused on the factors that shape enrollment decisions, or on the overall impact of specific programs. But few have attended to how the presence or absence of aid actually affects students? decisions about their education. As the researchers Sara Goldrick-Rab, of the University of Wisconsin at Madison, and Douglas N. Harris, of Tulane University, recently argued in a paper on improving education research, we simply do not know enough about which kinds of financial-aid programs work best, for which students, and in what ways.