For Nobel Prizes, it's abundantly clear that people from and/or working at top schools win them vastly more than small schools by people that were at the school when the work was done. [1] Harvard has around 150. Many of the top schools have around 100. Ohio State, despite being much bigger [2,3], has 4, and is much more in line with most state (right below top tier) schools.

If you want to challenge that the top schools have much more productive researchers (and those making significant breakthroughs) on average, feel free to present evidence. Any metric I can find for which I can get enough information implies otherwise.

[1] http://en.wikipedia.org/wiki/List_of_Nobel_laureates_by_univ...

[2] http://en.wikipedia.org/wiki/Harvard_University

[3] http://www.osu.edu/osutoday/stuinfo.php