<p>The idea of ranking colleges on a one-size-fits-all scale is silly to begin with. It is even sillier when the criteria and the weightings are arbitrary, as in the USN report. However, that does not mean that frosh retention is unimportant. The top colleges can limit their admissions to students who are highly likely to stay with the program, who have the financial resources to stay in school (either from their families, or from financial aid), and who are likely to succeed academically. The less prominent competitors have to settle for some students they might not have otherwise admitted. Those are higher risk candidates, and more of them drop out or transfer.</p>
<p>So frosh retention tells you where a college stands on those measures. Like any aggregate, it does not, in itself, distinguish financial, academic, fit, and personal reasons for students leaving. So it is a useful data point, but small differences, on the order of a few percent, mean little.</p>