Yeah, part of my original point was that the equation is inherently arbitrary. Imagine an equation like this:
(A x X) + (B x Y) + (C x Z) ....
and say that X is NIH dollars, Y is Nobel prizes, and Z is the weight of the admissions director.
If you make a small change in one of the coefficients A, B, C,... you would come up with totally different rankings. Who decides what the coefficients are and how does they relate to real-world educational value, even though X, Y, and Z are "hard numbers"?
And obviously a top 10 school is better than a non-top 50 school in so many categories... but my point is that even 3, 4, 5, 6 places different may mean nothing.