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Related papers: MG/OPT and MLMC for Robust Optimization of PDEs

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We consider (stochastic) softmax policy gradient (PG) methods for bandits and tabular Markov decision processes (MDPs). While the PG objective is non-concave, recent research has used the objective's smoothness and gradient domination…

Machine Learning · Computer Science 2024-10-01 Michael Lu , Matin Aghaei , Anant Raj , Sharan Vaswani

Finding effective ways to exploit parallel computing to accelerate Markov chain Monte Carlo methods is an important problem in Bayesian computation and related disciplines. In this paper, we consider the zeroth-order setting where the…

Computation · Statistics 2026-01-28 Francesco Pozza , Giacomo Zanella

This paper studies multi-level stochastic approximation algorithms. Our aim is to extend the scope of the multilevel Monte Carlo method recently introduced by Giles (Giles 2008) to the framework of stochastic optimization by means of…

Probability · Mathematics 2014-08-12 Noufel Frikha

This paper presents multilevel hybrid transport (MLHT) methods for solving the neutral-particle Boltzmann transport equation. The proposed MLHT methods are formulated on a sequence of spatial grids using a multilevel Monte Carlo (MLMC)…

Numerical Analysis · Mathematics 2026-05-12 Vincent N. Novellino , Dmitriy Y. Anistratov

The multilevel Monte Carlo (MLMC) method has been used for a wide variety of stochastic applications. In this paper we consider its use in situations in which input random variables can be replaced by similar approximate random variables…

Numerical Analysis · Mathematics 2022-04-08 Mike Giles , Oliver Sheridan-Methven

Optimizing highly complex cost/energy functions over discrete variables is at the heart of many open problems across different scientific disciplines and industries. A major obstacle is the emergence of many-body effects among certain…

A number of optimal decision problems with uncertainty can be formulated into a stochastic optimal control framework. The Least-Squares Monte Carlo (LSMC) algorithm is a popular numerical method to approach solutions of such stochastic…

Computational Finance · Quantitative Finance 2019-01-23 Zhiyi Shen , Chengguo Weng

We propose a multi-level method to increase the accuracy of machine learning algorithms for approximating observables in scientific computing, particularly those that arise in systems modeled by differential equations. The algorithm relies…

Numerical Analysis · Mathematics 2020-07-06 Kjetil O. Lye , Siddhartha Mishra , Roberto Molinaro

We analyze the convergence rate of the multiplicative gradient (MG) method for PET-type problems with $m$ component functions and an $n$-dimensional optimization variable. We show that the MG method has an $O(\ln(n)/t)$ convergence rate, in…

Optimization and Control · Mathematics 2022-09-28 Renbo Zhao

In this article we develop a multi-grid multi-level Monte Carlo (MGMLMC) method for the stochastic Stokes-Darcy interface model with random hydraulic conductivity both in the porous media domain and on the interface. Because the randomness…

Numerical Analysis · Mathematics 2019-03-07 Zhipeng Yang , Xiaoming He , Li Zhang , Ju Ming

We consider the problem of estimating the probability of a large loss from a financial portfolio, where the future loss is expressed as a conditional expectation. Since the conditional expectation is intractable in most cases, one may…

Numerical Analysis · Mathematics 2020-11-25 Zhenghang Xu , Zhijian He , Xiaoqun Wang

This work presents an efficient approach for accelerating multilevel Markov Chain Monte Carlo (MCMC) sampling for large-scale problems using low-fidelity machine learning models. While conventional techniques for large-scale Bayesian…

Machine Learning · Statistics 2024-05-21 Sohail Reddy , Hillary Fairbanks

We present a combination technique based on mixed differences of both spatial approximations and quadrature formulae for the stochastic variables to solve efficiently a class of Optimal Control Problems (OCPs) constrained by random partial…

Numerical Analysis · Mathematics 2024-03-29 Fabio Nobile , Tommaso Vanzan

We propose a multilevel Markov chain Monte Carlo (MCMC) method for the Bayesian inference of random field parameters in PDEs using high-resolution data. Compared to existing multilevel MCMC methods, we additionally consider level-dependent…

Numerical Analysis · Mathematics 2025-08-19 Pieter Vanmechelen , Geert Lombaert , Giovanni Samaey

In this work, we present, analyze, and implement a class of Multi-Level Markov chain Monte Carlo (ML-MCMC) algorithms based on independent Metropolis-Hastings proposals for Bayesian inverse problems. In this context, the likelihood function…

Numerical Analysis · Mathematics 2021-05-06 Juan Pablo Madrigal-Cianci , Fabio Nobile , Raul Tempone

This work describes a domain embedding technique between two non-matching meshes used for generating realizations of spatially correlated random fields with applications to large-scale sampling-based uncertainty quantification. The goal is…

Numerical Analysis · Mathematics 2017-12-20 Sarah Osborn , Patrick Zulian , Thomas Benson , Umberto Villa , Rolf Krause , Panayot S. Vassilevski

We present an efficient algorithm for the inference of stochastic block models in large networks. The algorithm can be used as an optimized Markov chain Monte Carlo (MCMC) method, with a fast mixing time and a much reduced susceptibility to…

Data Analysis, Statistics and Probability · Physics 2014-01-14 Tiago P. Peixoto

Accurate estimates of long-term risk probabilities and their gradients are critical for many stochastic safe control methods. However, computing such risk probabilities in real-time and in unseen or changing environments is challenging.…

Systems and Control · Electrical Eng. & Systems 2024-08-20 Zhuoyuan Wang , Yorie Nakahira

Robust optimisation is a well-established framework for optimising functions in the presence of uncertainty. The inherent goal of this problem is to identify a collection of inputs whose outputs are both desirable for the decision maker,…

Optimization and Control · Mathematics 2025-05-27 Ben Tu , Nikolas Kantas , Robert M. Lee , Behrang Shafei

Monte Carlo methods play important part in modern statistical physics. The application of these methods suffer from two main difficulties.The first is caused by the relatively small number of particles that can participate in any numerical…

Statistical Mechanics · Physics 2007-05-23 A. Brandt , V. Ilyin