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arXiv · 2103.00996

Asymmetric Differential Privacy

Shun Takagi·Yang Cao·Masatoshi Yoshikawa
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Abstract

Differential privacy (DP) is getting attention as a privacy definition when publishing statistics of a dataset. This paper focuses on the limitation that DP inevitably causes two-sided error, which is not desirable for epidemic analysis such as how many COVID-19 infected individuals visited location A. For example, consider publishing misinformation that many infected people did not visit location A, which may lead to miss decision-making that expands the epidemic. To fix this issue, we propose a relaxation of DP, called asymmetric differential privacy (ADP). We show that ADP can provide reasonable privacy protection while achieving one-sided error. Finally, we conduct experiments to evaluate the utility of proposed mechanisms for epidemic analysis using a real-world dataset, which shows the practicality of our mechanisms.

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Shun Takagi, Yang Cao, Masatoshi Yoshikawa. 2021-03-01. Asymmetric Differential Privacy. https://arxiv.org/abs/2103.00996

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