tend to cluster together, indicating that the combinations of these edges discriminate cases from controls. The cluster tree on the left side shows the relationship among the edges. The bottom five edges (indicated by green in the left color bar) are over-expressed in cases and are positively correlated with each other. The sixth edge (Po2-Pz and O2-Oz) is anti-correlated with the other five edges. This classifier was cross-validated across the four sets of subjects, corresponding to the four datasets that were pooled for this study. On average, the classifier accurately distinguished 81% of MDD from healthy control subjects.
