{ "id": "2011.10797", "version": "v1", "published": "2020-11-21T14:14:12.000Z", "updated": "2020-11-21T14:14:12.000Z", "title": "Adversarial Classification: Necessary conditions and geometric flows", "authors": [ "Nicolas Garcia Trillos", "Ryan Murray" ], "categories": [ "cs.LG", "cs.CR", "math.AP", "stat.ML" ], "abstract": "We study a version of adversarial classification where an adversary is empowered to corrupt data inputs up to some distance $\\varepsilon$, using tools from variational analysis. In particular, we describe necessary conditions associated with the optimal classifier subject to such an adversary. Using the necessary conditions, we derive a geometric evolution equation which can be used to track the change in classification boundaries as $\\varepsilon$ varies. This evolution equation may be described as an uncoupled system of differential equations in one dimension, or as a mean curvature type equation in higher dimension. In one dimension we rigorously prove that one can use the initial value problem starting from $\\varepsilon=0$, which is simply the Bayes classifier, in order to solve for the global minimizer of the adversarial problem. Numerical examples illustrating these ideas are also presented.", "revisions": [ { "version": "v1", "updated": "2020-11-21T14:14:12.000Z" } ], "analyses": { "keywords": [ "necessary conditions", "adversarial classification", "geometric flows", "mean curvature type equation", "geometric evolution equation" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }