论文标题
具有高维逆问题的超图结构的分布式块状吉布斯采样器
A Distributed Block-Split Gibbs Sampler with Hypergraph Structure for High-Dimensional Inverse Problems
论文作者
论文摘要
基于抽样的算法是在反问题上执行贝叶斯推断的经典方法。它们为估计器提供了相关的可信度间隔,以量化估计器的不确定性。尽管这些方法几乎不能扩展到高维问题,但它们最近与优化技术(例如近端和分裂方法)配对以解决此问题。这种方法为分布式采样器铺平了道路,从而使计算使推理更加可扩展和更快。我们引入了一个分布式的吉布斯采样器(SGS),以有效地解决涉及与线性运算符组成的多个平滑和非平滑函数的分布的问题。所提出的方法利用了最近的近似增强技术,让人联想到原始偶的优化方法。它与区块坐标方法进一步结合,将原始变量和双变量分为块,从而导致分布式块坐标SGS。所得的算法利用了所涉及的线性操作员的超图结构,以在受控的通信成本下有效地将变量分配给多个工人。它容纳了几个分布式架构,例如单个程序多个数据和客户端服务器架构。大图像脱毛问题的实验表明,在少数时间内使用可信度间隔的高质量估计方法的提出方法的性能。可以在线获得复制实验的补充材料。
Sampling-based algorithms are classical approaches to perform Bayesian inference in inverse problems. They provide estimators with the associated credibility intervals to quantify the uncertainty on the estimators. Although these methods hardly scale to high dimensional problems, they have recently been paired with optimization techniques, such as proximal and splitting approaches, to address this issue. Such approaches pave the way to distributed samplers, splitting computations to make inference more scalable and faster. We introduce a distributed Split Gibbs sampler (SGS) to efficiently solve such problems involving distributions with multiple smooth and non-smooth functions composed with linear operators. The proposed approach leverages a recent approximate augmentation technique reminiscent of primal-dual optimization methods. It is further combined with a block-coordinate approach to split the primal and dual variables into blocks, leading to a distributed block-coordinate SGS. The resulting algorithm exploits the hypergraph structure of the involved linear operators to efficiently distribute the variables over multiple workers under controlled communication costs. It accommodates several distributed architectures, such as the Single Program Multiple Data and client-server architectures. Experiments on a large image deblurring problem show the performance of the proposed approach to produce high quality estimates with credibility intervals in a small amount of time. Supplementary material to reproduce the experiments is available online.