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ROC curve equivalence using the Kolmogorov–Smirnov test. PRL, vol. 34, 470-475, 2013. Andrew P. Bradley Univ. of Queensland, Australia. ROC_1 » ROC_2 AUC_1 » AUC_2 AUC_1 » AUC_2 ROC_1 » ROC_2 AUC_1 » AUC_2 ROC_1 » ROC_2. The AUC problem.
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ROC curve equivalence using the Kolmogorov–Smirnov test PRL, vol. 34, 470-475, 2013 Andrew P. Bradley Univ. of Queensland, Australia ROC_1 » ROC_2 AUC_1 » AUC_2 AUC_1 »AUC_2 ROC_1 »ROC_2 AUC_1 »AUC_2 ROC_1 »ROC_2 Coffee Talk
The AUC problem • The AUC is a fundamentally incoherent measure for comparing ROC curves (see David Hand, 2005, 2009, 2013) • Bradley: Don’t throw away the ROC because of this • Bradley: What we need is a test of the equivalence of two ROC curves: H0: ROC_1 » ROC_2 Use the Kolmogorov–Smirnov test by finding the two most different operating points. Coffee Talk
The KS test for two distributions 1 H0: Fy(x) = Fz(x) Fz(x) Fy(x) D D = maxx|Fy(x)-Fz(x)| 0 If D > Z(p,n) : reject H0 Coffee Talk
The KS test for two classifiers (Bradley) The classifier scores y and z have to be shifted to the same domain, e.g. by shifting z to the domain of y Coffee Talk
Example AUCy = AUCz, ROCy ≠ ROCz Coffee Talk
Conclusion Correct if in sy and szy are based on the same set of objects but just applied to different classifiers and some domain shift?? Coffee Talk