Working Papers
Working Papers
Wasserstein-p Central Limit Theorem Rates: From Local Dependence to Markov Chains
Yixuan Zhang, and Qiaomin Xie
Preliminary version: ACM SIGMETRICS 2026 (Best Paper Award Finalist)
On the Peril of (Even a Little) Nonstationarity in Satisficing Regret Minimization
Yixuan Zhang, Ruihao Zhu, and Qiaomin Xie
A Unified Lyapunov Analysis for Sub-quadratic-SGD: Applications to Robust and Quantile Regression
Yixuan Zhang, Lucy Huo, and Qiaomin Xie
Preliminary version: ACM SIGMETRICS 2025
Journal Revisions and Publications
Memory, Nonlinearity, and Drift–Contraction in Stochastic Approximation with a Constant Stepsize
Yixuan Zhang, Lucy Huo, and Qiaomin Xie
Major revision at Mathematics of Operations Research.
Preliminary version: NeurIPS 2024 (Spotlight)
Prelimit Coupling and Steady-State Convergence of Constant-stepsize Nonsmooth Contractive SA
Yixuan Zhang, Lucy Huo, Yudong Chen, and Qiaomin Xie
Operations Research, 2026
Preliminary version: ACM SIGMETRICS 2024
Conference Publications
Wasserstein-p Central Limit Theorem Rates: From Local Dependence to Markov Chains
Yixuan Zhang, and Qiaomin Xie
ACM SIGMETRICS 2026 (Best Paper Award Finalist)
Contextual Online Pricing with (Biased) Offline Data
Yixuan Zhang, Ruihao Zhu, and Qiaomin Xie
NeurIPS 2025
A Piecewise Lyapunov Analysis of Sub-quadratic SGD: Applications to Robust and Quantile Regression
Yixuan Zhang, Lucy Huo, Yudong Chen, and Qiaomin Xie
ACM SIGMETRICS 2025
The Collusion of Memory and Nonlinearity in Stochastic Approximation With Constant Stepsize
Lucy Huo, Yixuan Zhang, Yudong Chen, and Qiaomin Xie
NeurIPS 2024 (Spotlight)
Prelimit Coupling and Steady-State Convergence of Constant-stepsize Nonsmooth Contractive SA
Yixuan Zhang, Lucy Huo, Yudong Chen, and Qiaomin Xie
ACM SIGMETRICS 2024 [video]
Constant Stepsize Q-learning: Distributional Convergence, Bias and Extrapolation
Yixuan Zhang, and Qiaomin Xie
Reinforcement Learning Conference 2024