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arXiv · 2406.14304

A Variational Characterization of $H$-Mutual Information and its Application to Computing $H$-Capacity

Akira Kamatsuka·Koki Kazama·Takahiro Yoshida
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Abstract

$H$-mutual information ($H$-MI) is a wide class of information leakage measures, where $H=(\eta, F)$ is a pair of monotonically increasing function $\eta$ and a concave function $F$, which is a generalization of Shannon entropy. $H$-MI is defined as the difference between the generalized entropy $H$ and its conditional version, including Shannon mutual information (MI), Arimoto MI of order $\alpha$, $g$-leakage, and expected value of sample information. This study presents a variational characterization of $H$-MI via statistical decision theory. Based on the characterization, we propose an alternating optimization algorithm for computing $H$-capacity.

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Akira Kamatsuka, Koki Kazama, Takahiro Yoshida. 2024-06-20. A Variational Characterization of $H$-Mutual Information and its Application to Computing $H$-Capacity. https://arxiv.org/abs/2406.14304

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