activity
20232026
collaborators

19 papers

cs.LG2026

AdaFlash: Adaptive Speculative Decoding via On-Policy Distilled Diffusion Drafters

Yu-Yang Qian, Hao-Cong Wu, Chen Chen +4

Speculative decoding, in which a lightweight draft model first generates a draft sequence that is then verified by the target model, has become a prevalent paradigm for acceleratin…

cs.LG2026

Nonlinear Bandit

Tianshuo Zheng, Ting Wu, Zhi-Hua Zhou +1

In this paper we first study the problem of generalized linear bandit (GLB) under heavy-tailed noise. The characteristics of heavy-tailed distributions are widely observed in real-…

cs.LG2026

Online Learning with Gradient-Variation Interval Regret

Yan-Feng Xie, Shuche Wang, Peng Zhao +1

This paper investigates non-stationary online learning using the metric of interval regret, which requires an online algorithm to perform well over every time interval. We propose…

cs.LG2026

Robust Length Prediction: A Perspective from Heavy-Tailed Prompt-Conditioned Distributions

Jing Wang, Yu-Yang Qian, Ke Xue +3

Output-length prediction is important for efficient LLM serving, as it directly affects batching, memory reservation, and scheduling. For prompt-only length prediction, most existi…

cs.LG2026

Dynamic Regret via Discounted-to-Dynamic Reduction with Applications to Curved Losses and Adam Optimizer

Yan-Feng Xie, Yu-Jie Zhang, Peng Zhao +1

We study dynamic regret minimization in non-stationary online learning, with a primary focus on follow-the-regularized-leader (FTRL) methods. FTRL is important for curved losses an…

cs.DB2026

AeroSketch: Near-Optimal Time Matrix Sketch Framework for Persistent, Sliding Window, and Distributed Streams

Hanyan Yin, Dongxie Wen, Jiajun Li +4

Many real-world matrix datasets arrive as high-throughput vector streams, making it impractical to store or process them in their entirety. To enable real-time analytics under limi…

cs.LG2025

A Simple, Optimal and Efficient Algorithm for Online Exp-Concave Optimization

Yi-Han Wang, Peng Zhao, Zhi-Hua Zhou

Online eXp-concave Optimization (OXO) is a fundamental problem in online learning, where the goal is to minimize regret when loss functions are exponentially concave. The standard…

cs.LG2025

Adaptivity and Universality: Problem-dependent Universal Regret for Online Convex Optimization

Peng Zhao, Yu-Hu Yan, Hang Yu +1

Universal online learning aims to achieve optimal regret guarantees without requiring prior knowledge of the curvature of online functions. Existing methods have established minima…

cs.LG2025

Optimistic Online-to-Batch Conversions for Accelerated Convergence and Universality

Yu-Hu Yan, Peng Zhao, Zhi-Hua Zhou

In this work, we study offline convex optimization with smooth objectives, where the classical Nesterov's Accelerated Gradient (NAG) method achieves the optimal accelerated converg…

cs.LG2025

Dual Adaptivity: Universal Algorithms for Minimizing the Adaptive Regret of Convex Functions

Lijun Zhang, Wenhao Yang, Guanghui Wang +2

To deal with changing environments, a new performance measure -- adaptive regret, defined as the maximum static regret over any interval, was proposed in online learning. Under the…

cs.LG2025

TreeLoRA: Efficient Continual Learning via Layer-Wise LoRAs Guided by a Hierarchical Gradient-Similarity Tree

Yu-Yang Qian, Yuan-Ze Xu, Zhen-Yu Zhang +2

Many real-world applications collect data in a streaming environment, where learning tasks are encountered sequentially. This necessitates continual learning (CL) to update models…

cs.LG2025

Heavy-Tailed Linear Bandits: Huber Regression with One-Pass Update

Jing Wang, Yu-Jie Zhang, Peng Zhao +1

We study the stochastic linear bandits with heavy-tailed noise. Two principled strategies for handling heavy-tailed noise, truncation and median-of-means, have been introduced to h…

cs.LG2025

Provably Efficient Online RLHF with One-Pass Reward Modeling

Long-Fei Li, Yu-Yang Qian, Peng Zhao +1

Reinforcement Learning from Human Feedback (RLHF) has shown remarkable success in aligning Large Language Models (LLMs) with human preferences. Traditional RLHF methods rely on a f…

cs.LG2024

Near-Optimal Dynamic Regret for Adversarial Linear Mixture MDPs

Long-Fei Li, Peng Zhao, Zhi-Hua Zhou

We study episodic linear mixture MDPs with the unknown transition and adversarial rewards under full-information feedback, employing dynamic regret as the performance measure. We s…

cs.LG2024

Gradient-Variation Online Learning under Generalized Smoothness

Yan-Feng Xie, Peng Zhao, Zhi-Hua Zhou

Gradient-variation online learning aims to achieve regret guarantees that scale with variations in the gradients of online functions, which has been shown to be crucial for attaini…

cs.LG2024

Provably Efficient Reinforcement Learning with Multinomial Logit Function Approximation

Long-Fei Li, Yu-Jie Zhang, Peng Zhao +1

We study a new class of MDPs that employs multinomial logit (MNL) function approximation to ensure valid probability distributions over the state space. Despite its significant ben…

cs.LG2024

Improved Algorithm for Adversarial Linear Mixture MDPs with Bandit Feedback and Unknown Transition

Long-Fei Li, Peng Zhao, Zhi-Hua Zhou

We study reinforcement learning with linear function approximation, unknown transition, and adversarial losses in the bandit feedback setting. Specifically, we focus on linear mixt…

cs.LG2023

Universal Online Learning with Gradient Variations: A Multi-layer Online Ensemble Approach

Yu-Hu Yan, Peng Zhao, Zhi-Hua Zhou

In this paper, we propose an online convex optimization approach with two different levels of adaptivity. On a higher level, our approach is agnostic to the unknown types and curva…

cs.LG2023

Stochastic Approximation Approaches to Group Distributionally Robust Optimization and Beyond

Lijun Zhang, Haomin Bai, Peng Zhao +2

This paper investigates group distributionally robust optimization (GDRO) with the goal of learning a model that performs well over different distributions. First, we formulate…