Appendix A Related Work of AUC Optimization

To this end, how to optimize the AUC performance has raised wide attention. As shown in Fig.3(a), given an open-set sample ( x AUC suffers from the inconsistency property III. To be specific, according to the prediction process described in Sec.2, if we select As shown in Fig.3(c), we have OpenAUC(h,r) OpenAUC( h, r) = 1 N C.5 Proof for Proposition 8 Proposition 8. Optimizing OpenAUC is equivalent to the following risk minimization problem: min Meanwhile, the hyperparameter λ is searched in { 0.1, 0 .2 During the test phase, open-set samples are available. In this section, we present the empirical results on fine-grained datasets.