论文标题
随机优化方法的统一收敛定理
A Unified Convergence Theorem for Stochastic Optimization Methods
论文作者
论文摘要
在这项工作中,我们提供了一种基本的统一收敛定理,用于得出一系列随机优化方法的预期和几乎确定的收敛结果。我们的统一定理仅需要验证几种代表性条件,并且不适合任何特定算法。作为直接应用,我们在更一般的设置下恢复了随机梯度方法(SGD)和随机改组(RR)的预期收敛结果。此外,我们为非平滑非凸优化问题的随机近端梯度方法(Prox-SGD)和基于随机模型的方法(SMM)建立了新的预期和几乎确定的收敛结果。这些应用程序表明,我们的统一定理为广泛的随机优化方法提供了插件类型的收敛分析和强大的收敛保证。
In this work, we provide a fundamental unified convergence theorem used for deriving expected and almost sure convergence results for a series of stochastic optimization methods. Our unified theorem only requires to verify several representative conditions and is not tailored to any specific algorithm. As a direct application, we recover expected and almost sure convergence results of the stochastic gradient method (SGD) and random reshuffling (RR) under more general settings. Moreover, we establish new expected and almost sure convergence results for the stochastic proximal gradient method (prox-SGD) and stochastic model-based methods (SMM) for nonsmooth nonconvex optimization problems. These applications reveal that our unified theorem provides a plugin-type convergence analysis and strong convergence guarantees for a wide class of stochastic optimization methods.