# Optimal Alternating Regret for Online Learning and Games

arXiv: https://arxiv.org/abs/2608.24731 · HTML: https://mlsanity.com/paper/2608.24731/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- Builds on 22 of its 35 references that are in the map.
- First posted on arXiv 25 Aug 2026.

## Builds on (most cited first, 22 of 22)

- [Introduction to Online Convex Optimization](https://mlsanity.com/paper/1909.05207/) (2019)
- [Online Learning: A Modern Introduction Using Convex Optimization](https://mlsanity.com/paper/1912.13213/) (2019)
- [Fast Convergence of Regularized Learning in Games](https://mlsanity.com/paper/1507.00407/) (2015)
- [Solving Large Imperfect Information Games Using CFR+](https://mlsanity.com/paper/1407.5042/) (2014)
- [Hedging in games: Faster convergence of external and swap regrets](https://mlsanity.com/paper/2006.04953/) (2020)
- [Near-Optimal No-Regret Learning for Correlated Equilibria in Multi-Player General-Sum Games](https://mlsanity.com/paper/2111.06008/) (2021)
- [Uncoupled Learning Dynamics with O(log T) Swap Regret in Multiplayer Games](https://mlsanity.com/paper/2204.11417/) (2022)
- [Near-optimal Local Convergence of Alternating Gradient Descent-Ascent for Minimax Optimization](https://mlsanity.com/paper/2102.09468/) (2021)
- [Finite Regret and Cycles with Fixed Step-Size via Alternating Gradient Descent-Ascent](https://mlsanity.com/paper/1907.04392/) (2019)
- [Near-Optimal No-Regret Learning Dynamics for General Convex Games](https://mlsanity.com/paper/2206.08742/) (2022)
- [Doubly Optimal No-Regret Learning in Monotone Games](https://mlsanity.com/paper/2301.13120/) (2023)
- [Alternating Mirror Descent for Constrained Min-Max Games](https://mlsanity.com/paper/2206.04160/) (2022)
- [Near-Optimal Policy Optimization for Correlated Equilibrium in General-Sum Markov Games](https://mlsanity.com/paper/2401.15240/) (2024)
- [Negative Stepsizes Make Gradient-Descent-Ascent Converge](https://mlsanity.com/paper/2505.01423/) (2025)
- [Faster Rates for No-Regret Learning in General Games via Cautious Optimism](https://mlsanity.com/paper/2503.24340/) (2025)
- [Fundamental Benefit of Alternating Updates in Minimax Optimization](https://mlsanity.com/paper/2402.10475/) (2024)
- [Cautious Optimism: A Meta-Algorithm for Near-Constant Regret in General Games](https://mlsanity.com/paper/2506.05005/) (2025)
- [Alternating Regret for Online Convex Optimization](https://mlsanity.com/paper/2502.12529/) (2025)
- [Sublogarithmic Swap Regret in Multiplayer General-Sum Games via Hybrid Regularization](https://mlsanity.com/paper/2608.04149/) (2026)
- [A Riemannian Alternating Descent Ascent Algorithmic Framework for Nonconvex-Linear Minimax Problems on Riemannian Manifolds](https://mlsanity.com/paper/2409.19588/) (2024)
- [Continuous-Time Analysis of Heavy Ball Momentum in Min-Max Games](https://mlsanity.com/paper/2505.19537/) (2025)
- [On the O(1/T) Convergence of Alternating Gradient Descent-Ascent in Bilinear Games](https://mlsanity.com/paper/2510.03855/) (2025)

## Built on by (most cited first, 2 of 2)

- [Constant regret in general games via higher-order optimism](https://mlsanity.com/paper/2609.04113/) (2026)
- [A Horizon-Independent Regret Bound for Optimistic Hedge in General-Sum Games](https://mlsanity.com/paper/2609.22839/) (2026)

## Abstract (arXiv)

We settle the minimax-optimal alternating regret, a regret notion motivated by alternating learning dynamics in games, for both online linear optimization (OLO) and online convex optimization (OCO). For OLO over the probability simplex Deltad, we give an algorithm with O(log d) alternating regret that remains a constant for any time horizon T, and a matching lower bound. Our constant regret bound significantly improves previous results with O(log 2/3d · T1/3) regret [Cevher, Cutkosky, Kavis, Piliouras, Skoulakis, Viano, NeurIPS 2023, Hait, Li, Luo, Zhang, COLT 2025]. As a result, we obtain alternating learning dynamics with O(log d /T) convergence to Nash equilibria in two-player zero-sum games and O(log d /T) convergence to coarse correlated equilibria in two-player general-sum games. This is the first uncoupled learning dynamics with O(1/T) convergence to CCE in two-player general-sum games, while all prior works suffer additional log T factors. For general OCO over a d-dimensional compact convex set, we give an algorithm with O(dlog (1+T/d)) alternating regret, improving the previous best of widetildeO(d2/3T1/3). We also prove a matching lower bound of Omega(dlog (1+T/d)), showing that the Omega(log T) factor is unavoidable.
