Figure 4.

Mean and standard deviation of A(f), ${\hat{A}}_{\mathit{LOO}}(f),{\hat{A}}_{\mathit{LPO}}(f)$ and ${\hat{A}}_{\mathit{TLPO}}(f)$ over 617 repetitions as the class fraction varies. AUC: area under the receiver operating characteristic curve; A(f): true AUC of the classifier; ${\hat{A}}_{\mathit{LOO}}(f)$: leave-one-out AUC estimate; ${\hat{A}}_{\mathit{LPO}}(f)$: leave-pair-out AUC estimate; ${\hat{A}}_{\mathit{TLPO}}(f)$: tournament leave-pair-out AUC estimate; PCa: prostate cancer.