Relative cost curves: An alternative to AUC and an extension to 3-class problems

Abstract

to specify exactly the consequences or costs of misclassifications. This paper is devoted to Relative Cost Curves (RCC) ‐ a graphical technique for visualising the performance of binary classifiers over the full range of possible relative misclassification costs. This curve provides helpful information to choose the best set of classifiers or to estimate misclassification costs if those are not known precisely. In this paper, the concept of Area Above the RCC (AAC) is introduced, a scalar measure of classifier performance under unequal misclassification costs problem. We also extend RCC to multicategory problems when misclassification costs depend only on the true class.