English
Related papers

Related papers: Adaptivity of Stochastic Gradient Methods for Nonc…

200 papers

We propose a new stochastic first-order algorithmic framework to solve stochastic composite nonconvex optimization problems that covers both finite-sum and expectation settings. Our algorithms rely on the SARAH estimator introduced in…

Optimization and Control · Mathematics 2019-04-01 Nhan H. Pham , Lam M. Nguyen , Dzung T. Phan , Quoc Tran-Dinh

We develop and analyze a variant of the SARAH algorithm, which does not require computation of the exact gradient. Thus this new method can be applied to general expectation minimization problems rather than only finite sum problems. While…

Optimization and Control · Mathematics 2020-08-28 Lam M. Nguyen , Katya Scheinberg , Martin Takáč

In this paper, we study and analyze the mini-batch version of StochAstic Recursive grAdient algoritHm (SARAH), a method employing the stochastic recursive gradient, for solving empirical loss minimization for the case of nonconvex losses.…

Machine Learning · Statistics 2017-05-23 Lam M. Nguyen , Jie Liu , Katya Scheinberg , Martin Takáč

In this paper, we propose a StochAstic Recursive grAdient algoritHm (SARAH), as well as its practical variant SARAH+, as a novel approach to the finite-sum minimization problems. Different from the vanilla SGD and other modern stochastic…

Machine Learning · Statistics 2017-09-08 Lam M. Nguyen , Jie Liu , Katya Scheinberg , Martin Takáč

We introduce two new stochastic conjugate frameworks for a class of nonconvex and possibly also nonsmooth optimization problems. These frameworks are built upon Stochastic Recursive Gradient Algorithm (SARAH) and we thus refer to them as…

Optimization and Control · Mathematics 2023-10-23 Jiangshan Wang , Zheng Peng

In this note we propose a new variant of the hybrid variance-reduced proximal gradient method in [7] to solve a common stochastic composite nonconvex optimization problem under standard assumptions. We simply replace the independent…

Optimization and Control · Mathematics 2020-08-21 Deyi Liu , Lam M. Nguyen , Quoc Tran-Dinh

Stochastic-gradient-based optimization has been a core enabling methodology in applications to large-scale problems in machine learning and related areas. Despite the progress, the gap between theory and practice remains significant, with…

Optimization and Control · Mathematics 2021-01-01 Lihua Lei , Michael I. Jordan

We present AI-SARAH, a practical variant of SARAH. As a variant of SARAH, this algorithm employs the stochastic recursive gradient yet adjusts step-size based on local geometry. AI-SARAH implicitly computes step-size and efficiently…

Machine Learning · Computer Science 2022-02-02 Zheng Shi , Abdurakhmon Sadiev , Nicolas Loizou , Peter Richtárik , Martin Takáč

This work considers the non-convex finite sum minimization problem. There are several algorithms for such problems, but existing methods often work poorly when the problem is badly scaled and/or ill-conditioned, and a primary goal of this…

In this work, we consider convex optimization problems with smooth objective function and nonsmooth functional constraints. We propose a new stochastic gradient algorithm, called Stochastic Halfspace Approximation Method (SHAM), to solve…

Optimization and Control · Mathematics 2024-12-04 Nitesh Kumar Singh , Ion Necoara

We propose ZeroSARAH -- a novel variant of the variance-reduced method SARAH (Nguyen et al., 2017) -- for minimizing the average of a large number of nonconvex functions $\frac{1}{n}\sum_{i=1}^{n}f_i(x)$. To the best of our knowledge, in…

Machine Learning · Computer Science 2021-10-12 Zhize Li , Slavomír Hanzely , Peter Richtárik

The total complexity (measured as the total number of gradient computations) of a stochastic first-order optimization algorithm that finds a first-order stationary point of a finite-sum smooth nonconvex objective function $F(w)=\frac{1}{n}…

Optimization and Control · Mathematics 2019-04-24 Lam M. Nguyen , Marten van Dijk , Dzung T. Phan , Phuong Ha Nguyen , Tsui-Wei Weng , Jayant R. Kalagnanam

In machine learning, nonconvex optimization problems with multiple local optimums are often encountered. Graduated Optimization Algorithm (GOA) is a popular heuristic method to obtain global optimums of nonconvex problems through…

Machine Learning · Computer Science 2017-07-11 Li Chen , Shuisheng Zhou , Zhuan Zhang

High-order tensor methods that employ Taylor-based local models (of degree $p\ge 3$) within adaptive regularization frameworks have been recently proposed for both convex and nonconvex optimization problems. They have been shown to have…

Optimization and Control · Mathematics 2024-04-19 Wenqi Zhu , Coralia Cartis

This paper considers decentralized minimization of $N:=nm$ smooth non-convex cost functions equally divided over a directed network of $n$ nodes. Specifically, we describe a stochastic first-order gradient method, called GT-SARAH, that…

Optimization and Control · Mathematics 2021-09-21 Ran Xin , Usman A. Khan , Soummya Kar

This paper focuses on stochastic proximal gradient methods for optimizing a smooth non-convex loss function with a non-smooth non-convex regularizer and convex constraints. To the best of our knowledge we present the first non-asymptotic…

Optimization and Control · Mathematics 2019-05-27 Michael R. Metel , Akiko Takeda

We introduce a hybrid stochastic estimator to design stochastic gradient algorithms for solving stochastic optimization problems. Such a hybrid estimator is a convex combination of two existing biased and unbiased estimators and leads to…

Optimization and Control · Mathematics 2019-05-16 Quoc Tran-Dinh , Nhan H. Pham , Dzung T. Phan , Lam M. Nguyen

We here adapt an extended version of the adaptive cubic regularisation method with dynamic inexact Hessian information for nonconvex optimisation in [3] to the stochastic optimisation setting. While exact function evaluations are still…

Numerical Analysis · Mathematics 2020-09-15 Stefania Bellavia , Gianmarco Gurioli

We analyze stochastic gradient algorithms for optimizing nonconvex, nonsmooth finite-sum problems. In particular, the objective function is given by the summation of a differentiable (possibly nonconvex) component, together with a possibly…

Optimization and Control · Mathematics 2018-12-04 Zhize Li , Jian Li

In this paper, we propose Adjusted Shuffling SARAH, a novel algorithm that integrates shuffling strategies into the recursive SARAH framework using a dynamic weighting mechanism to enhance exploration. We analyze the algorithm under two…

Optimization and Control · Mathematics 2026-05-28 Duc Toan Nguyen , Trang H. Tran , Lam M. Nguyen
‹ Prev 1 2 3 10 Next ›