^^^ I believe that the departmental rankings, while largely anecdotal, are less subjective than the academic reputation rankings. Faculty within disciplines have specific knowledge of departments in other universities, by keeping up with publications, learning about moves or retirement of star faculty, and interviewing new PhD’s for tenure-track jobs. Provosts and deans are much more removed from the academic life of universities other than their own, although they may “keep up” through professional networks and some publications.
Yet the academic reputation metric in US News correlates much more strongly with the US News rankings than the departmental rankings, and doubtless has more influence with prospective students. Please note that in our “alternative rankings” we use academic reputation, grad rates, and class sizes only to illustrate that filtering out the finance metrics used by US News yields a very different ranking. If we were to come up with a true alternative ranking of our own based on the best metrics we could find, we would use departmental rankings instead of academic reputation.