The performances of SVM and logistic regression in the different confidence levels of PPIs. a) "No Net" means the prediction models used ADR vs. drug target facts; "5 Stars" means we used PPIs in HAPPI under the confidence of 5 stars level; "4 Stars UP" means we used PPIs in HAPPI under the confidence of 4 to 5 stars level; and so forth. A red solid line represents the performance with SVM, while a blue solid line shows the performance with logistic regression. A red dotted line means we expanded the drug target network by replacing the PPI networks with random networks as control experiments or a base line of the performances with SVM, while a blue dotted line illustrates the effect of using logistic regression. AUC: area under ROC curve. ACC: accuracy. SEN: sensitivity. SPE: specificity. b) This box plot comparisons performances from using "2 Stars UP" PPI-expanding networks versus SVM under different p-value criteria in the feature selection.