activity
20192026
most citedAdaptivity and Non-stationarity: Problem-dependent Dynamic Regret for Online Convex Optimization

12 citations · 37 across the 12 of their papers we have counts for

collaborators

12 papers

cs.LG2026

Efficient Multinomial Logistic Bandit via Frequent Directions

Linzhe He, Yu-Jie Zhang, Sifan Yang +1

This paper studies efficient online algorithms for multinomial logistic bandits (MLogB), where the feedback distribution over outcomes follows a multinomial logistic model of…

cs.LG2026

Near-Optimal Regret in Adversarial Kernel Bandits

Yu-Jie Zhang, Hao Qiu, Jonathan Scarlett +1

We study the adversarial kernel bandit problem, in which the loss at each round is induced by an arbitrary bounded element of a reproducing kernel Hilbert space (RKHS). We propose…

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.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.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.LG2023★ 2 cited

Optimistic Online Mirror Descent for Bridging Stochastic and Adversarial Online Convex Optimization

Sijia Chen, Yu-Jie Zhang, Wei-Wei Tu +2

Stochastically Extended Adversarial (SEA) model is introduced by Sachs et al. [2022] as an interpolation between stochastic and adversarial online convex optimization. Under the sm…

cs.LG2023★ 2 cited

Adapting to Continuous Covariate Shift via Online Density Ratio Estimation

Yu-Jie Zhang, Zhen-Yu Zhang, Peng Zhao +1

Dealing with distribution shifts is one of the central challenges for modern machine learning. One fundamental situation is the covariate shift, where the input distributions of da…

cs.LG2022

Adapting to Online Label Shift with Provable Guarantees

Yong Bai, Yu-Jie Zhang, Peng Zhao +2

The standard supervised learning paradigm works effectively when training data shares the same distribution as the upcoming testing samples. However, this stationary assumption is…

cs.LG2021★ 12 cited

Adaptivity and Non-stationarity: Problem-dependent Dynamic Regret for Online Convex Optimization

Peng Zhao, Yu-Jie Zhang, Lijun Zhang +1

We investigate online convex optimization in non-stationary environments and choose dynamic regret as the performance measure, defined as the difference between cumulative loss inc…

cs.LG2020★ 12 cited

Dynamic Regret of Convex and Smooth Functions

Peng Zhao, Yu-Jie Zhang, Lijun Zhang +1

We investigate online convex optimization in non-stationary environments and choose the dynamic regret as the performance measure, defined as the difference between cumulative loss…

cs.LG2020

Exploratory Machine Learning with Unknown Unknowns

Peng Zhao, Jia-Wei Shan, Yu-Jie Zhang +1

In conventional supervised learning, a training dataset is given with ground-truth labels from a known label set, and the learned model will classify unseen instances to known labe…

cs.LG2019★ 9 cited

An Unbiased Risk Estimator for Learning with Augmented Classes

Yu-Jie Zhang, Peng Zhao, Zhi-Hua Zhou

This paper studies the problem of learning with augmented classes (LAC), where augmented classes unobserved in the training data might emerge in the testing phase. Previous studies…