The fact is, neither selectivity rankings nor aggregate statistics for any school can really tell candidates with any degree of precision the likelihood that they will be admitted. Owing to many factors other than the ones cited above, including the desire to admit athletes of a certain caliber, to admit the children of alumni, and to have diverse student bodies, the selectivity of the very top schools is highly uneven. That unevenness—the different standards applied to different types of candidates being evaluated by any single school on this list—may well swamp any differences among schools' overall selectivity scores.
If what the rankings conceal is telling, so, too, is how they change over time—or, rather, how they fail to change. (When enduring change does occur, the explanation may be cultural and reflect nothing about a school's inherent quality. America's urban renaissance, for instance, which has made city schools more attractive to students, might lie behind the steady rise of Columbia and Penn and the slow fall-off by Dartmouth and Cornell.) One of the more striking characteristics of the top-fifty list is how chronological it turns out to be. That is, one good predictor of a school's selectivity rank is nothing more complicated than the date of its founding. The average founding years of the top five, ten, twenty-five, fifty, and 100 most selective schools in the nation are 1767, 1785, 1822, 1839, and 1850, respectively. Eight of the first ten schools established in the United States are today among the nation's fifty most selective schools. Of the 128 doctoral universities, liberal-arts colleges, and service academies founded in the whole of the past century, only six can make the same claim. For all the talk of "hot" and "cold" schools, it is difficult to think of another industry in which historical legacy carries as much weight, or brand image appears as immutable. All but nine of the top fifty schools in 1992 are still in the top fifty today; and only four schools have broken in or out of the top twenty-five during the same period. By comparison, the top fifty companies in Forbes's 2002 ranking of the nation's largest companies are significantly different from the fifty that topped the 1992 list. (Twelve companies were acquired in the intervening years. And thirteen—more than one third of the remainder—have fallen off the list.) Against the backdrop of an economic culture built around competition and creative destruction, the hierarchy of elite schools appears curiously frozen in time.
And yet, at least in economic terms, a brand-name education appears to mean less than people think. In a 1999 study conducted for the National Bureau of Economic Research, Alan B. Krueger and Stacy Berg Dale showed that the selectivity of the schools students attended—given students of similar background and aptitude—made little difference in terms of their later earnings. Specifically, Krueger and Dale compared people who had attended highly selective schools with people who had gotten into comparable schools but had chosen less selective ones. They found that those in the former group earned no more than those in the latter.
Still, there is something inherently attractive about trying to rate schools based on their selectivity. Such a rating seems to provide clarity. But the clarity is an illusion. There may be good reasons for an individual student to prefer Harvard, the fifth school on this list, to Colgate, the fiftieth. But the fact that Harvard (on average) is harder to get into should not be predominant among them.