A New Algorithm for Computing $\alpha$-Capacity

Akira Kamatsuka; Koki Kazama; Takahiro Yoshida

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arXiv · 2405.07368

A New Algorithm for Computing $\alpha$-Capacity

Akira Kamatsuka·Koki Kazama·Takahiro Yoshida

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Abstract

The problem of computing $\alpha$-capacity for $\alpha>1$ is equivalent to that of computing the correct decoding exponent. Various algorithms for computing them have been proposed, such as Arimoto and Jitsumatsu--Oohama algorithm. In this study, we propose a novel alternating optimization algorithm for computing the $\alpha$-capacity for $\alpha>1$ based on a variational characterization of the Augustin--Csisz{\'a}r mutual information. A comparison of the convergence performance of these algorithms is demonstrated through numerical examples.

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Akira Kamatsuka, Koki Kazama, Takahiro Yoshida. 2024-05-12. A New Algorithm for Computing $\alpha$-Capacity. https://arxiv.org/abs/2405.07368

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