Accuracy of qualitative GI prediction. The histograms compare combinations of classifiers and feature sets when seeking a classification of gene pairs into positive, negative and neutral interactions. The combinations are compared in terms of the area under the ROC curve (AUC) and the area under the precision-recall curve (AUPR). (a, b) Predictions of negative interactions, measured by the AUC (a) and AUPR (b). (c, d) Predictions of positive interactions using AUC (c) and AUPR (d). The diffusion kernel method  uses only the topology of the GI network and does not exploit the other features.