# Finite Regret and Cycles with Fixed Step-Size via Alternating Gradient Descent-Ascent

arXiv: https://arxiv.org/abs/1907.04392 · HTML: https://mlsanity.com/paper/1907.04392/

## Key facts

- Cited by 29 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 9 Jul 2019.

## Built on by (most cited first, 29 of 29)

- [Near-optimal Local Convergence of Alternating Gradient Descent-Ascent for Minimax Optimization](https://mlsanity.com/paper/2102.09468/) (2021)
- [Exploration-Exploitation in Multi-Agent Competition: Convergence with Bounded Rationality](https://mlsanity.com/paper/2106.12928/) (2021)
- [Alternating Mirror Descent for Constrained Min-Max Games](https://mlsanity.com/paper/2206.04160/) (2022)
- [Complex Momentum for Optimization in Games](https://mlsanity.com/paper/2102.08431/) (2021)
- [Learning in Matrix Games can be Arbitrarily Complex](https://mlsanity.com/paper/2103.03405/) (2021)
- [Follow-the-Regularized-Leader Routes to Chaos in Routing Games](https://mlsanity.com/paper/2102.07974/) (2021)
- [Online Learning in Periodic Zero-Sum Games](https://mlsanity.com/paper/2111.03377/) (2021)
- [Sampling without Replacement Leads to Faster Rates in Finite-Sum Minimax Optimization](https://mlsanity.com/paper/2206.02953/) (2022)
- [Solving Min-Max Optimization with Hidden Structure via Gradient Descent Ascent](https://mlsanity.com/paper/2101.05248/) (2021)
- [Minimax Optimization with Smooth Algorithmic Adversaries](https://mlsanity.com/paper/2106.01488/) (2021)
- [Lyapunov Exponents for Diversity in Differentiable Games](https://mlsanity.com/paper/2112.14570/) (2021)
- [On the Initialization for Convex-Concave Min-max Problems](https://mlsanity.com/paper/2103.00284/) (2021)
- [Accelerated Proximal Alternating Gradient-Descent-Ascent for Nonconvex Minimax Machine Learning](https://mlsanity.com/paper/2112.11663/) (2021)
- [Nash, Conley, and Computation: Impossibility and Incompleteness in Game Dynamics](https://mlsanity.com/paper/2203.14129/) (2022)
- [A Single-Loop Robust Policy Gradient Method for Robust Markov Decision Processes](https://mlsanity.com/paper/2406.00274/) (2024)
- [Online Optimization in Games via Control Theory: Connecting Regret, Passivity and Poincar'e Recurrence](https://mlsanity.com/paper/2106.04748/) (2021)
- [Continuous-Time Analysis of Heavy Ball Momentum in Min-Max Games](https://mlsanity.com/paper/2505.19537/) (2025)
- [Recursive Reasoning in Minimax Games: A Level k Gradient Play Method](https://mlsanity.com/paper/2210.16482/) (2022)
- [Convergence of two-timescale gradient descent ascent dynamics: finite-dimensional and mean-field perspectives](https://mlsanity.com/paper/2501.17122/) (2025)
- [Optimism Without Regularization: Constant Regret in Zero-Sum Games](https://mlsanity.com/paper/2506.16736/) (2025)
- [Optimal Alternating Regret for Online Learning and Games](https://mlsanity.com/paper/2608.24731/) (2026)
- [Competitive Gradient Optimization](https://mlsanity.com/paper/2205.14232/) (2022)
- [Constants of Motion: The Antidote to Chaos in Optimization and Game Dynamics](https://mlsanity.com/paper/2109.03974/) (2021)
- [Local Convergence of Gradient Methods for Min-Max Games: Partial Curvature Generically Suffices](https://mlsanity.com/paper/2305.17275/) (2023)
- [Chaos persists in large-scale multi-agent learning despite adaptive learning rates](https://mlsanity.com/paper/2306.01032/) (2023)
- [Characterizing Nash Equilibria in Zero-Sum Games: A Physics-Inspired, Parallelizable Approach with a Linear Number of Gradient Queries](https://mlsanity.com/paper/2507.11366/) (2025)
- [Understanding Dynamics of Adam in Zero-Sum Games: An ODE Approach](https://mlsanity.com/paper/2605.19392/) (2026)
- [Accelerated and Stable Convergence with Anchored Generalized Optimistic Method](https://mlsanity.com/paper/2606.21528/) (2026)
- [Minimax Alternating Regret for the Experts Problem and Online Convex Optimization](https://mlsanity.com/paper/2608.25182/) (2026)

## Abstract (arXiv)

Gradient descent is arguably one of the most popular online optimization methods with a wide array of applications. However, the standard implementation where agents simultaneously update their strategies yields several undesirable properties; strategies diverge away from equilibrium and regret grows over time. In this paper, we eliminate these negative properties by introducing a different implementation to obtain finite regret via arbitrary fixed step-size. We obtain this surprising property by having agents take turns when updating their strategies. In this setting, we show that an agent that uses gradient descent obtains bounded regret -- regardless of how their opponent updates their strategies. Furthermore, we show that in adversarial settings that agents' strategies are bounded and cycle when both are using the alternating gradient descent algorithm.
