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A Simple Fix to Mahalanobis Distance for Improving Near-OOD Detection

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arxiv 2106.09022 v1 pith:NMP6UOVP submitted 2021-06-16 cs.LG

A Simple Fix to Mahalanobis Distance for Improving Near-OOD Detection

classification cs.LG
keywords detectiondistancemahalanobissimplegenomicsimprovesnear-oodperformance
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
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Mahalanobis distance (MD) is a simple and popular post-processing method for detecting out-of-distribution (OOD) inputs in neural networks. We analyze its failure modes for near-OOD detection and propose a simple fix called relative Mahalanobis distance (RMD) which improves performance and is more robust to hyperparameter choice. On a wide selection of challenging vision, language, and biology OOD benchmarks (CIFAR-100 vs CIFAR-10, CLINC OOD intent detection, Genomics OOD), we show that RMD meaningfully improves upon MD performance (by up to 15% AUROC on genomics OOD).

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Cited by 24 Pith papers

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