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arXiv · 2306.12377

Geometric Algorithms for $k$-NN Poisoning

Diego Ihara Centurion·Karine Chubarian·Bohan Fan·Francesco Sgherzi·Thiruvenkadam S Radhakrishnan·Anastasios Sidiropoulos·Angelo Straight
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Abstract

We propose a label poisoning attack on geometric data sets against $k$-nearest neighbor classification. We provide an algorithm that can compute an $\varepsilon n$-additive approximation of the optimal poisoning in $n\cdot 2^{2^{O(d+k/\varepsilon)}}$ time for a given data set $X \in \mathbb{R}^d$, where $|X| = n$. Our algorithm achieves its objectives through the application of multi-scale random partitions.

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Diego Ihara Centurion, Karine Chubarian, Bohan Fan, Francesco Sgherzi, Thiruvenkadam S Radhakrishnan, Anastasios Sidiropoulos, Angelo Straight. 2023-06-21. Geometric Algorithms for $k$-NN Poisoning. https://arxiv.org/abs/2306.12377

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