The difference is that applicants by definition don’t have personal experience of how good the school is, it’s all perception. With page rank and citations the expectation is those linking to or citing something have read it and have reason to value it.
Same with students applying. They’re betting that students aren’t applying completely randomly to schools and that the research they do beforehand isn’t entirely noise and has some signal that will show up in the average.
I mean it’s a pretty darn conservative proposition to say “we think that averaged over the entire population of applicants that the schools that students spend their time applying to will trend, however small, to better schools.
Where the flip side of “it’s all noise and it’s impossible to evaluate a school better than flipping a coin without actually attending” is an incredibly strong assertion.
I'm in the UK, but my eldest is starting Uni this September and rankings played a huge role in her selection of colleges. Yes of course she looked at their prospectuses and visited a few of them, but the shortlist of the ones to look at and visit itself was based on rankings.
It's like the XKCD about Wikipedia entries being cited in articles, which get cited in papers, which then get cited in the same Wikipedia article.
