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arXiv · 2108.06797

Deep Adversarially-Enhanced k-Nearest Neighbors

Ren Wang·Tianqi Chen·Alfred Hero
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Abstract

Recent works have theoretically and empirically shown that deep neural networks (DNNs) have an inherent vulnerability to small perturbations. Applying the Deep k-Nearest Neighbors (DkNN) classifier, we observe a dramatically increasing robustness-accuracy trade-off as the layer goes deeper. In this work, we propose a Deep Adversarially-Enhanced k-Nearest Neighbors (DAEkNN) method which achieves higher robustness than DkNN and mitigates the robustness-accuracy trade-off in deep layers through two key elements. First, DAEkNN is based on an adversarially trained model. Second, DAEkNN makes predictions by leveraging a weighted combination of benign and adversarial training data. Empirically, we find that DAEkNN improves both the robustness and the robustness-accuracy trade-off on MNIST and CIFAR-10 datasets.

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Ren Wang, Tianqi Chen, Alfred Hero. 2021-08-15. Deep Adversarially-Enhanced k-Nearest Neighbors. https://arxiv.org/abs/2108.06797

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