A study by Avery, Glickman, Hoxby and Metrick proposes a new ranking system for U.S. colleges and universities based on student preference. They suggest in the study that their ranking system is not effected by financial aid.

Our ranking is...similar regardless of whether we control for variables, such as net cost, that vary among a college’s admits

They used Net Price of a college in order to determine if it had any impact on student decision making process. The issue with Net Price is it is an average--it does not begin to tell the story. No one has linked it to decision making of individual students. A student who goes to a school with a Net Price of $30,000 (on the very high side) and has a full ride (effective net price of $0) is making different decisions--economically.

College Net Price might get students in the door, but it does not make the sale.

For a full news article on the study see @erichoov at the Chronicle of Higher Ed.