Results of protein-protein interaction prediction by PIC. (a) Receiver operating characteristic (ROC) curves of PIC for S. cerevisiae (red), P. falciparum (green) and E. coli (blue). (b) Comparison of ROC curves in yeast for PIC (red), interolog mapping (INT, green), phylogenetic profiles (PGP, blue), Rosetta stone (ROS, dark blue), CAI coevolution (co-CAI, blue dotted line) and absolute CAI value (CAI, red dotted line). The dashed line shows the diagonal. The same comparison is shown using the precision-recall curves in Additional data file 10. For interolog mapping, phylogenetic profiles and Rosetta stone, data were retrieved from . FP, false positive; N, negative; P, positive; TP, true positive. Positive and negative test sets are as indicated in Table 1.