I think you just misread the data. The ones near the top are about the make-up of the departments, so CMU and Georgia Tech simply have a lot of professors. The tables at the bottom are about sources of professors (placements).
imjustatomato writes: Top computer science conferences typically have an award given to the best paper submitted to that conference. This web page compiles the best paper awards for 16 conferences since 1996, in artificial intelligence, HCI, databases, information retrieval, and theory. The institution that hold the most best paper awards? Stanford, followed by Microsoft Research, CMU, and the University of Washington.