Multi-Differential Fairness Auditor for Black Box Classifiers

Xavier Gitiaux; Huzefa Rangwala

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arXiv · 1903.07609

Multi-Differential Fairness Auditor for Black Box Classifiers

Xavier Gitiaux·Huzefa Rangwala

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Abstract

Machine learning algorithms are increasingly involved in sensitive decision-making process with adversarial implications on individuals. This paper presents mdfa, an approach that identifies the characteristics of the victims of a classifier's discrimination. We measure discrimination as a violation of multi-differential fairness. Multi-differential fairness is a guarantee that a black box classifier's outcomes do not leak information on the sensitive attributes of a small group of individuals. We reduce the problem of identifying worst-case violations to matching distributions and predicting where sensitive attributes and classifier's outcomes coincide. We apply mdfa to a recidivism risk assessment classifier and demonstrate that individuals identified as African-American with little criminal history are three-times more likely to be considered at high risk of violent recidivism than similar individuals but not African-American.

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Xavier Gitiaux, Huzefa Rangwala. 2019-03-18. Multi-Differential Fairness Auditor for Black Box Classifiers. https://arxiv.org/abs/1903.07609

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