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enter image description hereHi, my ROC curve seems weird because in most of the cases, the slope of ROC curve should decrease.

Can anyone help to interpret this? Thanks in advance.

M.K
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  • This answered question may also address your observation: https://stats.stackexchange.com/questions/66837/why-does-my-roc-curve-look-like-this-is-it-correct – Todd D Apr 20 '20 at 19:24

1 Answers1

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"Real" ROC curves should always be convex by construction. However, in empirical data, concavity can occur through noise. Pesce et al. (2010, Academic Radiology) discuss the phenomenon and investigate the implications of concave ROC curves on medical decisions. You may also be interested in this presentation by Gneiting et al. (2019).

Stephan Kolassa
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