Figure 1. Classification receiver operating characteristic curves (ROC).

Color curves indicate actual-model ROC (Left panel: ROC corresponding to the 10 actual-model feature selection repeats; Right panel: ROC corresponding to the classification of the validation sample). Example curves obtained from the null-model randomization procedures are also shown (left: reshuffling of group membership; right: reshuffling of the edges used as features). The central solid gray line depicts an ROC with an area under the curve close to the median of all permutations, whereas the lower and upper dotted gray lines represent ROC with areas under the curve close to percentiles 2.5 and 97.5, respectively, of the random distributions.