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I know that the ROC curve plots true positives vs false positives, but does it have any other interpretation, or is it just an arbitrary performance measure? Also, in the case of very unbalanced response variable's classes (say 10 to 1) is an AUC of 0.5 still a bad thing?


marked as duplicate by gung, Xi'an, kjetil b halvorsen, cbeleites, chl Jan 14 '15 at 9:37

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