Oracle-based Uniform Sampling from Convex Bodies
- URL: http://arxiv.org/abs/2510.02983v1
- Date: Fri, 03 Oct 2025 13:21:05 GMT
- Title: Oracle-based Uniform Sampling from Convex Bodies
- Authors: Thanh Dang, Jiaming Liang,
- Abstract summary: We propose new Markov chain Monte Carlo algorithms to sample a uniform distribution on a convex body $K$.<n>Our algorithms are based on the Alternating Sampling Framework/proximal sampler, which uses Gibbs sampling on an augmented distribution.
- Score: 2.087898608419977
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We propose new Markov chain Monte Carlo algorithms to sample a uniform distribution on a convex body $K$. Our algorithms are based on the Alternating Sampling Framework/proximal sampler, which uses Gibbs sampling on an augmented distribution and assumes access to the so-called restricted Gaussian oracle (RGO). The key contribution of this work is the efficient implementation of RGO for uniform sampling on $K$ via rejection sampling and access to either a projection oracle or a separation oracle on $K$. In both oracle cases, we establish non-asymptotic complexities to obtain unbiased samples where the accuracy is measured in R\'enyi divergence or $\chi^2$-divergence.
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