A Generalized Leakage Interpretation of Alpha-Mutual Information

Akira Kamatsuka; Takahiro Yoshida

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arXiv · 2601.09406

A Generalized Leakage Interpretation of Alpha-Mutual Information

Akira Kamatsuka·Takahiro Yoshida

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Abstract

This paper presents a unified interpretation of $\alpha$-mutual information ($\alpha$-MI) in terms of generalized $g$-leakage. Specifically, we present a novel interpretation of $\alpha$-MI within an extended framework for quantitative information flow based on adversarial generalized decision problems. This framework employs the Kolmogorov-Nagumo mean and the $q$-logarithm to characterize adversarial gain. Furthermore, we demonstrate that, within this framework, the parameter $\alpha$ can be interpreted as a measure of the adversary's risk aversion.

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Akira Kamatsuka, Takahiro Yoshida. 2026-01-14. A Generalized Leakage Interpretation of Alpha-Mutual Information. https://arxiv.org/abs/2601.09406

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