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arXiv · 2610.15853

Jensen-Bregman split Gibbs sampling

Nicolas Dobigeon·Mame Diarra Fall·Eric Barat
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Abstract

Split Gibbs sampling (SGS) is a versatile tool to sample from complex posterior distributions, such as those arising in imaging inverse problems. However, existing SGS instances are limited to quadratic variable couplings, restricting their applicability to Gaussian likelihoods. This letter genearalizes SGS to non-Euclidean geometry by introducing a coupling kernel defined through a Jensen-Bregman divergence. This framework not only enables posterior sampling in these settings but also unifies several \emph{ad hoc} sampling schemes from the literature under a principled theoretical foundation.

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Nicolas Dobigeon, Mame Diarra Fall, Eric Barat. 2026-10-11. Jensen-Bregman split Gibbs sampling. https://arxiv.org/abs/2610.15853

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