(a) For each of 10 random partitions of training cohorts into training and test sets we rank the genes according to their average Cox-scores over the N
training cohorts (N
= 3). (b) 1, Definition of MPI and evaluation of the optimal classifier(s) using the independent test sets of the training cohorts. 2, denotes the D-index of the top n-gene classifier for partition/realization p in test set of the training cohort s. 3, denotes the weighted average D-index over the test sets in the training cohorts where N
denotes the size of the test set of training cohort s. 4, The optimal classifier for each partition/realization p, , is defined by the number of top-ranked genes, n, that maximizes . (c) Validation of the optimal classifiers in completely independent external cohorts.