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20242026
most citedConstant Stepsize Q-learning: Distributional Convergence, Bias and Extrapolation

1 citations · 1 across the 9 of their papers we have counts for

collaborators

9 papers

math.PR2026

Gaussian Approximation in Wasserstein-p: Markovian Martingale Differences and Stochastic Approximation

Yixuan Zhang, Qiaomin Xie

We establish nonasymptotic Gaussian approximation bounds in higher-order Wasserstein distance , , for deterministic matrix-weighted sums of multivariate Poisson martin…

stat.ML2026

On the Peril of (Even a Little) Nonstationarity in Satisficing Regret Minimization

Yixuan Zhang, Ruihao Zhu, Qiaomin Xie

Motivated by the principle of satisficing in decision-making, we study satisficing regret guarantees for nonstationary -armed bandits. We show that in the general realizable, pi…

math.OC2026

Optimization with Parametric Variational Inequality Constraints on a Moving Set Based on a Smoothing Method

Xiaojun Chen, Jin Zhang, Yixuan Zhang

This paper focuses on optimization problems constrained by Parametric Variational Inequalities (PVI) defined on a moving set. Unlike most existing works on mathematical programs wi…

math.PR2026

Wasserstein-p Central Limit Theorem Rates: From Local Dependence to Markov Chains

Yixuan Zhang, Qiaomin Xie

Non-asymptotic central limit theorem (CLT) rates play a central role in modern machine learning and operations research. In this paper, we study CLT rates for multivariate dependen…

cs.LG2025

Contextual Online Pricing with (Biased) Offline Data

Yixuan Zhang, Ruihao Zhu, Qiaomin Xie

We study contextual online pricing with biased offline data. For the scalar price elasticity case, we identify the instance-dependent quantity that measures how far the offli…

stat.ML2025

A Piecewise Lyapunov Analysis of Sub-quadratic SGD: Applications to Robust and Quantile Regression

Yixuan Zhang, Dongyan Huo, Yudong Chen +1

Motivated by robust and quantile regression problems, we investigate the stochastic gradient descent (SGD) algorithm for minimizing an objective function that is locally strong…

stat.ML2024

The Collusion of Memory and Nonlinearity in Stochastic Approximation With Constant Stepsize

Dongyan Huo, Yixuan Zhang, Yudong Chen +1

In this work, we investigate stochastic approximation (SA) with Markovian data and nonlinear updates under constant stepsize . Existing work has primarily focused on either i.…

stat.ML2024

Prelimit Coupling and Steady-State Convergence of Constant-stepsize Nonsmooth Contractive SA

Yixuan Zhang, Dongyan Huo, Yudong Chen +1

Motivated by Q-learning, we study nonsmooth contractive stochastic approximation (SA) with constant stepsize. We focus on two important classes of dynamics: 1) nonsmooth contractiv…

stat.ML2024★ 1 cited

Constant Stepsize Q-learning: Distributional Convergence, Bias and Extrapolation

Yixuan Zhang, Qiaomin Xie

Stochastic Approximation (SA) is a widely used algorithmic approach in various fields, including optimization and reinforcement learning (RL). Among RL algorithms, Q-learning is pa…