Eighty percent of all tenure and tenure-track faculty at Ph.D. granting institutions come from a subset of just 20 percent of universities; 5 to 23 percent of faculty members were employed at universities more "prestigious" than their own doctoral-granting institution.

Prof. Aaron Clauset discusses what this means for institutions trying to reach faculty diversity goals, how this trend is often fueled by a "prestige economy," and what trustees and regents should think about when asked to approve new Ph.D. programs.