This R package calculates the probability that a set of independent gamma (or normal) variates attains a certain order. For the Gamma case, it takes as input a vector of shape and scale parameters. Of course, all orders are equally probable (1/n!) if the parameters are shared among the variables, but the rank probability is much more difficult to compute in the general case.
The package deploys a special dynamic programming scheme described in a manuscript in preparation.
#Installation
library(devtools)
install_github("wiscstatman/GammaRank")