Reflexive Rankings

New Ranking System Based On Choice ... They lay out a system that ranks colleges on how they perform in one kind of head-to-head competition they contend says a lot about a school and can be measured: the battle for students who are admitted to several colleges. ... In their proposal, the economists sidestep the tricky question of what makes a good college. Instead, they assume top high school students know best, and they simply report their choices. Of the students admitted to, say, both Brown University and the University of Pennsylvania, how many choose each place? It is the same principle in the Zagat restaurant guides: Don't try to grade the food, just say whether a lot of people like it or not.

Using student preferences is a bit trickier than this article makes it out to be. One of the main functions served by college rankings is to act as input to the very choices that this new ranking is based on. That's why colleges care about their rank -- being ranked high influences incoming students and their parents, making good students more likely to enroll. A good set of indicators of the type U.S. News compiles has additional utility for prospectives as well. Now, this may not be the best way to pick a school (I looked at the rankings, but wound up going to the third-ranked of the four schools I got into). But it certainly adds a complication to the use of revealed preferences to create rankings.