activity
20102026
most citedLearning with a Strong Adversary

255 citations · 2.4k across the 127 of their papers we have counts for

collaborators

130 papers

cs.LG2026

On the Two Faces of Adam in Separable Linear Classification

Chen Fan, Csaba Szepesvári

We consider the behavior of deterministic, full-batch, bias-corrected Adam in separable linear classification with softmax parametrization under log-loss. In this setting, under a…

cs.LG2024

Stochastic Gradient Succeeds for Bandits

Jincheng Mei, Zixin Zhong, Bo Dai +3

We show that the \emph{stochastic gradient} bandit algorithm converges to a \emph{globally optimal} policy at an rate, even with a \emph{constant} step size. Remarkably, g…

cs.LG2023

The Optimal Approximation Factors in Misspecified Off-Policy Value Function Estimation

Philip Amortila, Nan Jiang, Csaba Szepesvári

Theoretical guarantees in reinforcement learning (RL) are known to suffer multiplicative blow-up factors with respect to the misspecification error of function approximation. Yet,…

cs.LG2023

Context-lumpable stochastic bandits

Chung-Wei Lee, Qinghua Liu, Yasin Abbasi-Yadkori +3

We consider a contextual bandit problem with contexts and actions. In each round , the learner observes a random context and chooses an action based on its pas…

cs.LG2023

Regularization and Variance-Weighted Regression Achieves Minimax Optimality in Linear MDPs: Theory and Practice

Toshinori Kitamura, Tadashi Kozuno, Yunhao Tang +12

Mirror descent value iteration (MDVI), an abstraction of Kullback-Leibler (KL) and entropy-regularized reinforcement learning (RL), has served as the basis for recent high-performi…

cs.LG2023

Optimistic Natural Policy Gradient: a Simple Efficient Policy Optimization Framework for Online RL

Qinghua Liu, Gellért Weisz, András György +2

While policy optimization algorithms have played an important role in recent empirical success of Reinforcement Learning (RL), the existing theoretical understanding of policy opti…