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arXiv · 2601.11927

Exact Redundancy for Symmetric Rate-Distortion

Sharang M. Sriramu·Aaron B. Wagner
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Abstract

For variable-length coding with an almost-sure distortion constraint, Zhang et al. show that for discrete sources the redundancy is upper bounded by $\log n/n$ and lower bounded (in most cases) by $\log n/(2n)$, ignoring lower order terms. For a uniform source with a distortion measure satisfying certain symmetry conditions, we show that $\log n/(2n)$ is achievable and that this cannot be improved even if one relaxes the distortion constraint to be in expectation rather than with probability one.

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Sharang M. Sriramu, Aaron B. Wagner. 2026-01-17. Exact Redundancy for Symmetric Rate-Distortion. https://arxiv.org/abs/2601.11927

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