paper-with-me

Papers

On the Initialization for Convex-Concave Min-max Problems

2021-02-27 · Mingrui Liu, Francesco Orabona

Convex-concave min-max problems are ubiquitous in machine learning, and people usually utilize first-order methods (e.g., gradient descent ascent) to find the optimal solution. One feature which separates convex-concave min-max problems from convex minimization problems is that the best known convergence rates for min-max problems have an explicit dependence on the size of the domain, rather than on the distance between initial point and the optimal solution. This means that the convergence speed does not have any improvement even if the algorithm starts from the optimal solution, and hence, is oblivious to the initialization. Here, we show that strict-convexity-strict-concavity is sufficient to get the convergence rate to depend on the initialization. We also show how different algorithms can asymptotically achieve initialization-dependent convergence rates on this class of functions. Furthermore, we show that the so-called "parameter-free" algorithms allow to achieve improved initialization-dependent asymptotic rates without any learning rate to tune. In addition, we utilize this particular parameter-free algorithm as a subroutine to design a new algorithm, which achieves a novel non-asymptotic fast rate for strictly-convex-strictly-concave min-max problems with a growth condition and H{\"o}lder continuous solution mapping. Experiments are conducted to verify our theoretical findings and demonstrate the effectiveness of the proposed algorithms.

📄 PDF Abstract BibTeX arXiv:2103.00284

Code (0)

등록된 구현이 없습니다.

Similar Papers 제목 키워드 기반

The Landscape of the Proximal Point Method for Nonconvex-Nonconcave Minimax Optimization

2020-06-15 · Benjamin Grimmer, Haihao Lu, Pratik Worah, Vahab Mirrokni

Minimax optimization has become a central tool in machine learning with applications in robust optimization, reinforcement learning, GANs, etc. These applications are often nonconvex-nonconcave, but the existing theory i…

Last-Iterate Convergence of Optimistic Multiplicative Weight Update

2026-06-10 · Francesco Orabona arxiv

Optimistic Gradient Descent Ascent (OGDA) and Optimistic Multiplicative-Weights Update (OMWU) are two very popular algorithms to solve convex/concave saddle-point problems, where OMWU is the non-Euclidean, entropic versi…

A Unified Single-loop Alternating Gradient Projection Algorithm for Nonconvex-Concave and Convex-Nonconcave Minimax Problems

2020-06-03 · Zi Xu, Huiling Zhang, Yang Xu, Guanghui Lan

Much recent research effort has been directed to the development of efficient algorithms for solving minimax problems with theoretical convergence guarantees due to the relevance of these problems to a few emergent appli…

STay-ON-the-Ridge: Guaranteed Convergence to Local Minimax Equilibrium in Nonconvex-Nonconcave Games

2022-10-18 · Constantinos Daskalakis, Noah Golowich, Stratis Skoulakis, Manolis Zampetakis

Min-max optimization problems involving nonconvex-nonconcave objectives have found important applications in adversarial training and other multi-agent learning settings. Yet, no known gradient descent-based method is gu…

Completely Parameter-Free Single-Loop Algorithms for Nonconvex-Concave Minimax Problems

2024-07-31 · Junnan Yang, Huiling Zhang, Zi Xu

Due to their importance in various emerging applications, efficient algorithms for solving minimax problems have recently received increasing attention. However, many existing algorithms require prior knowledge of the pr…