24 karma · joined January 22, 2020
Note that decimal numbers represented as a floating point numbers on a computer are actually rational numbers due to limited precision. So converting decimal numbers to fractions, both stored on a computer, means converting a fraction with potentially large numerator and/or denominator to a simpler fraction, say, one with a far smaller denonimator.
For example, an approximation to pi is 3.14159265358979323844, which is the same thing as 314159265358979323844/10^20 (trivial approximation). Using these algorithms we can covert this fraction to a simpler fraction under different approximation criteria such as a bound on the approximation error or a bound on the magnitude of the denominator. For this example, we then get various approximations to pi such as 22/7, 355/113, ...
For a recent and comprehensive coverage, you can check out D. Knuth's fascicle as part of his well-known book. The BDD fascicle and other fascicles are available at http://www.cs.utsa.edu/~wagner/knuth/ .
I don't think the paper gives any hints on us dividing universities into classes and comparing. Would love to know how you reached that conclusion.
At the same time, yes, we could have divided universities into different classes: research vs liberal arts, this vs. that state, big vs. small size, etc. These are all trivial groupings but none of these would change the conclusions of this paper. For all practical purposes, we could easily have replaced the university names with labels like U1, U2, ... and still the conclusions would not change. What matters is how a weight-based composite index can be gamed and the paper does show that in multiple ways. Pls review the ILP formulations yourself and run them on the dataset of your choice.