RWRtools CV (Cross Validation) performs cross validation on a single gene set, finding the Random Walk with Restart (RWR) rank of the left-out genes. Cross validation methods include k-fold (default method, k = 5), leave-one-out (loo) (leave only one gene from the gene set out and use other genes to find its rank), or singletons (one gene is used to find the ranks of all other genes in the gene set). Descriptions of provided multiplexes can be found "here".
A demo Narrative for both RWRtools apps can be found here.