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Related papers: Gradient-Free Methods for Saddle-Point Problem

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In this paper, we study the problem of escaping from saddle points in smooth nonconvex optimization problems subject to a convex set $\mathcal{C}$. We propose a generic framework that yields convergence to a second-order stationary point of…

Machine Learning · Computer Science 2018-10-10 Aryan Mokhtari , Asuman Ozdaglar , Ali Jadbabaie

We show that convex-concave Lipschitz stochastic saddle point problems (also known as stochastic minimax optimization) can be solved under the constraint of $(\epsilon,\delta)$-differential privacy with \emph{strong (primal-dual) gap} rate…

Machine Learning · Computer Science 2023-06-30 Raef Bassily , Cristóbal Guzmán , Michael Menart

In this paper, we consider non-smooth stochastic convex optimization with two function evaluations per round under infinite noise variance. In the classical setting when noise has finite variance, an optimal algorithm, built upon the…

We propose and analyze several stochastic gradient algorithms for finding stationary points or local minimum in nonconvex, possibly with nonsmooth regularizer, finite-sum and online optimization problems. First, we propose a simple proximal…

Machine Learning · Computer Science 2022-08-23 Zhize Li , Jian Li

In practice, optimization tasks have some structure that allows developing new algorithms for every problem with faster convergence rates. Using the structure of optimization tasks, we can propose algorithms with more optimistic convergence…

Optimization and Control · Mathematics 2020-09-01 Alexander Tyurin

We consider the problem of convergence to a saddle point of a concave-convex function via gradient dynamics. Since first introduced by Arrow, Hurwicz and Uzawa in [1] such dynamics have been extensively used in diverse areas, there are,…

Optimization and Control · Mathematics 2019-08-06 Thomas Holding , Ioannis Lestas

We consider a class of non-smooth strongly convex-strongly concave saddle point problems in a decentralized setting without a central server. To solve a consensus formulation of problems in this class, we develop an inexact primal dual…

Machine Learning · Computer Science 2023-09-14 Chhavi Sharma , Vishnu Narayanan , P. Balamurugan

This study develops a fixed-time convergent saddle point dynamical system for solving min-max problems under a relaxation of standard convexity-concavity assumption. In particular, it is shown that by leveraging the dynamical systems…

Optimization and Control · Mathematics 2022-07-28 Kunal Garg , Mayank Baranwal

We show that the primal-dual gradient method, also known as the gradient descent ascent method, for solving convex-concave minimax problems can be viewed as an inexact gradient method applied to the primal problem. The gradient, whose exact…

Optimization and Control · Mathematics 2020-07-03 Shuo Han

We give nearly matching upper and lower bounds on the oracle complexity of finding $\epsilon$-stationary points ($\| \nabla F(x) \| \leq\epsilon$) in stochastic convex optimization. We jointly analyze the oracle complexity in both the local…

Machine Learning · Computer Science 2019-02-15 Dylan J. Foster , Ayush Sekhari , Ohad Shamir , Nathan Srebro , Karthik Sridharan , Blake Woodworth

In this study, we consider an optimization problem with uncertainty dependent on decision variables, which has recently attracted attention due to its importance in machine learning and pricing applications. In this problem, the gradient of…

Optimization and Control · Mathematics 2024-12-31 Yuya Hikima , Akiko Takeda

We consider optimization methods for convex minimization problems under inexact information on the objective function. We introduce inexact model of the objective, which as a particular cases includes $(\delta,L)$ inexact oracle and…

In this paper we present an inexact zeroth-order method suitable for the solution nonsmooth and nonconvex stochastic composite optimization problems, in which the objective is split into a real-valued Lipschitz continuous stochastic…

Optimization and Control · Mathematics 2025-12-11 Spyridon Pougkakiotis , Dionysis Kalogerias

We consider the closely related problems of bandit convex optimization with two-point feedback, and zero-order stochastic convex optimization with two function evaluations per round. We provide a simple algorithm and analysis which is…

Machine Learning · Computer Science 2015-08-03 Ohad Shamir

We study the iteration complexity of the optimistic gradient descent-ascent (OGDA) method and the extra-gradient (EG) method for finding a saddle point of a convex-concave unconstrained min-max problem. To do so, we first show that both…

Optimization and Control · Mathematics 2020-09-30 Aryan Mokhtari , Asuman Ozdaglar , Sarath Pattathil

In this paper we analyze a zeroth-order proximal stochastic gradient method suitable for the minimization of weakly convex stochastic optimization problems. We consider nonsmooth and nonlinear stochastic composite problems, for which…

Optimization and Control · Mathematics 2025-04-21 Spyridon Pougkakiotis , Dionysios S. Kalogerias

This paper addresses a class of nonsmooth and nonconvex optimization problems defined on complete Riemannian manifolds. The objective function has a composite structure, combining convex, differentiable, and lower semicontinuous terms,…

Optimization and Control · Mathematics 2025-11-19 Vitaliano S. Amaral , Marcio Antônio de A. Bortoloti , Jurandir O. Lopes , Gilson N. Silva

We propose a projection-free conditional gradient-type algorithm for smooth stochastic multi-level composition optimization, where the objective function is a nested composition of $T$ functions and the constraint set is a closed convex…

Optimization and Control · Mathematics 2022-10-11 Tesi Xiao , Krishnakumar Balasubramanian , Saeed Ghadimi

Gradient-based first-order convex optimization algorithms find widespread applicability in a variety of domains, including machine learning tasks. Motivated by the recent advances in fixed-time stability theory of continuous-time dynamical…

Machine Learning · Computer Science 2023-10-24 Mayank Baranwal , Param Budhraja , Vishal Raj , Ashish R. Hota

Large-scale saddle-point problems arise in such machine learning tasks as GANs and linear models with affine constraints. In this paper, we study distributed saddle-point problems (SPP) with strongly-convex-strongly-concave smooth…

Optimization and Control · Mathematics 2022-10-04 Dmitriy Metelev , Alexander Rogozin , Alexander Gasnikov , Dmitry Kovalev