TY - JOUR T1 - A Sharp Uniform-in-Time Error Estimate for Stochastic Gradient Langevin Dynamics AU - Li , Lei AU - Wang , Yuliang JO - CSIAM Transactions on Applied Mathematics VL - 4 SP - 711 EP - 759 PY - 2025 DA - 2025/09 SN - 6 DO - http://doi.org/10.4208/csiam-am.SO-2024-0039 UR - https://global-sci.org/intro/article_detail/csiam-am/24501.html KW - Random batch, Euler-Maruyama scheme, Fokker-Planck equation, log-Sobolev inequality. AB -

Abstract. We establish a sharp uniform-in-time error estimate for the stochastic gradient Langevin dynamics (SGLD), which is a widely-used sampling algorithm. Under mild assumptions, we obtain a uniform-in-time $\mathcal{O}(η^2)$ bound for the Kullback-Leibler divergence between the SGLD iteration and the Langevin diffusion, where $η$ is the step size (or learning rate). Our analysis is also valid for varying step sizes. Consequently, we are able to derive an $\mathcal{O}(\eta)$ bound for the distance between the invariant measures of the SGLD iteration and the Langevin diffusion, in terms of Wasserstein or total variation distances. Our result can be viewed as a significant improvement compared with existing analysis for SGLD in related literature.