Qizhou Wang

Qizhou Wang

I completed my PhD in the Department of Computer Science at Hong Kong Baptist University, where I was advised by Prof. Bo Han. My earlier research focused on building reliable and trustworthy machine learning systems, with work spanning OOD detection, OOD generalization, adversarial robustness, and learning with noisy labels. I am now broadly interested in LLM post-training and inference, including reinforcement learning, machine unlearning, and data curation. My recent projects are exploring agentic memory and long-context LLMs.

I am dedicated to collaborating with talented undergraduate students and helping them begin their research careers. Some of my junior collaborators have gone on to secure PhD positions at the University of Hong Kong, the University of Melbourne, Mohamed bin Zayed University of Artificial Intelligence, the University of Waterloo, and the Max Planck Institute for Software Systems. I am always open to new collaborations and would be happy to hear from you if you are interested.
News
[2026.4] I will serve as an Area Chair for the Position Paper Track at NeurIPS 2026.
[2026.3] I will serve as an Editorial Board Member for Machine Learning Journal.
[2026.2] One paper (OOD detection) is accepted by TPAMI. Congratulations to Zhaohui!
[2026.1] Five papers (unlearning and preference optimization) are accepted by ICLR 2026! Congratulations to Kemou, Zizhuo, Fengpeng, Liang, and Junfeng.
[2026.1] We will present a tutorial on Handling Out-of-Distribution Data in the Open World at the AAAI-26 Tutorial and Lab Forum.
Research Experience
2021–25

PhD in Computer Science

Department of Computer Science, Hong Kong Baptist University
Advised by Prof. Bo Han
Hong Kong

2025

Visiting PhD Student

Department of Computer Science, Cornell University
Advised by Prof. Kilian Q. Weinberger
Remote

2024

Visiting PhD Student

Imperfect Information Learning Team, RIKEN AIP
Advised by Prof. Masashi Sugiyama and Dr. Gang Niu
Tokyo

Selected Publications
Preprints
What Is Preference Optimization Doing, How and Why?
Y. Wang, Q. Wang, Z. Zhang, A. Li, G. Niu, B. Han, and M. Sugiyama
Arxiv, 2025
@article{yue2025what, title={What Is Preference Optimization Doing, How and Why?}, author={Wang, Yue and Wang, Qizhou and Zhang, Zizhuo and Li, Ang and Niu, Gang and Han, Bo and Sugiyama, Masashi}, journal={Arxiv Preprint}, year={2025} }
Conference
LLM Unlearning with LLM Beliefs
K. Li, Q. Wang, Y. Wang, F. Li, J. Liu, B. Han, and J. Zhou
ICLR 2026
@inproceedings{li2026llm, title={LLM Unlearning with LLM Beliefs}, author={Li, Kemou and Wang, Qizhou and Wang, Yue and Li, Fengpeng and Liu, Jun and Han, Bo and Zhou, Jiantao}, booktitle={International Conference on Learning Representations}, year={2026} }
Towards Understanding Valuable Preference Data for Large Language Model Alignment
Z. Zhang, Q. Wang, S. Ye, J. Zhu, J. Yao, B. Han, and M. Sugiyama
ICLR 2026
@inproceedings{zhang2026towards, title={Towards Understanding Valuable Preference Data for Large Language Model Alignment}, author={Zhang, Zizhuo and Wang, Qizhou and Ye, Shanshan and Zhu, Jianing and Yao, Jiangchao and Han, Bo and Sugiyama, Masashi}, booktitle={International Conference on Learning Representations}, year={2026} }
AEGIS: Adversarial Target-Guided Retention-Data-Free Robust Concept Erasure from Diffusion Models
F. Li, K. Li, Q. Wang, B. Han, and J. Zhou
ICLR 2026
@inproceedings{li2026AEGIS, title={AEGIS: Adversarial Target–Guided Retention-Data-Free Robust Concept Erasure from Diffusion Models}, author={Li, Fengpeng and Li, Kemou and Wang, Qizhou and Han, Bo and Zhou, Jiantao}, booktitle={International Conference on Learning Representations}, year={2026} }
EEPO: Exploration-Enhanced Policy Optimization via Sample-Then-Forget
L. Chen, X. Han, Q. Wang, B. Han, J. Bai, H. Schutze, and KF Wong
ICLR 2026
@inproceedings{chen2026eepo, title={EEPO: Exploration-Enhanced Policy Optimization via Sample-Then-Forget}, author={Liang Chen and Xueting Han and Qizhou Wang and Bo Han and Jing Bai and Hinrich Schutze and Kam-Fai Wong}, booktitle={International Conference on Learning Representations}, year={2026} }
Explainable LLM Unlearning through Reasoning
J. Liao, Q. Wang, S. Ye, X. Yu, L. Chen, and Z. Fang
ICLR 2026
@inproceedings{liao2026explainable, title={Explainable LLM Unlearning through Reasoning}, author={Liao, Junfeng and Wang, Qizhou and Ye, Shanshan and Yu, Xin and Chen, Ling and Fang, Zhen}, booktitle={International Conference on Learning Representations}, year={2026} }
Adaptive Localization of Knowledge Negation for Continual LLM Unlearning
A. Wuerkaixi, Q. Wang, S. Cui, W. Xu, B. Han, G. Niu, M. Sugiyama, and C. Zhang
ICML 2025
@inproceedings{wuerkaixi2025adaptive, title={Adaptive Localization of Knowledge Negation for Continual LLM Unlearning}, author={Wuerkaixi, Abudukelimu and Wang, Qizhou and Cui, Sen and Xu, Wutong and Han, Bo and Niu, Gang and Sugiyama, Masashi and Zhang, Changshui}, booktitle={International Conference on Machine Learning}, year={2025} }
Exploring Criteria of Loss Reweighting to Enhance LLM Unlearning
P. Yang, Q. Wang, Z. Huang, T. Liu, C. Zhang, and B. Han
ICML 2025
@inproceedings{yang2025exploring, title={Exploring Criteria of Loss Reweighting to Enhance LLM Unlearning}, author={Yang, Puning and Wang, Qizhou and Huang, Zhuo and Liu, Tongliang and Zhang, Chengqi and Han, Bo}, booktitle={International Conference on Machine Learning}, year={2025} }
GRU: Mitigating the Trade-off between Unlearning and Retention for Large Language Models
Y. Wang, Q. Wang, F. Liu, W. Huang, Y. Du, X. Du, and B. Han
ICML 2025
@inproceedings{wang2025gru, title={GRU: Mitigating the Trade-off between Unlearning and Retention for Large Language Models}, author={Wang, Yue and Wang, Qizhou and Liu, Feng and Huang, Wei and Du, Yali and Du, Xiaojiang and Han, Bo}, booktitle={International Conference on Machine Learning}, year={2025} }
Rethinking LLM Unlearning Objectives: A Gradient Perspective and Go Beyond
Q. Wang, J. Zhou, Z. Zhou, S. Shin, B. Han, and K. Q. Weinberger
ICLR 2025
@inproceedings{wang2025rethinking, title={Rethinking LLM Unlearning Objectives: A Gradient Perspective and Go Beyond}, author={Qizhou Wang and Jin Peng Zhou and Zhanke Zhou and Saebyeol Shin and Bo Han and Kilian Q Weinberger}, booktitle={International Conference on Learning Representations}, year={2025} }
Towards Effective Evaluations and Comparison for LLM Unlearning Methods
Q. Wang, B. Han, P. Yang, J. Zhu, T. Liu, and M. Sugiyama
ICLR 2025
@inproceedings{wang2025towards, title={Towards Effective Evaluations and Comparison for LLM Unlearning Methods}, author={Qizhou Wang and Bo Han and Puning Yang and Jianing Zhu and Tongliang Liu and Masashi Sugiyama}, booktitle={International Conference on Learning Representations}, year={2025} }
A Sober Look at the Robustness of CLIPs to Spurious Features
Q. Wang, Y. Lin, Y. Chen, L. Schmidt, B. Han, and T. Zhang
NeurIPS 2024
@inproceedings{wang2024clip, title={A Sober Look at the Robustness of CLIPs to Spurious Features}, author={Qizhou Wang and Yong Lin and Yongqiang Chen and Ludwig Schmidt and Bo Han and Tong Zhang}, booktitle={Advances in Neural Information Processing Systems}, year={2024} }
Learning to Augment Distributions for Out-of-distribution Detection
Q. Wang, Z. Fang, Y. Zhang, F. Liu, Y. Li, and B. Han
NeurIPS 2023
@inproceedings{wang2023learning, title={Learning to Augment Distributions for Out-of-distribution Detection}, author={Qizhou Wang and Zhen Fang and Yonggang Zhang and Feng Liu and Yixuan Li and Bo Han}, booktitle={Advances in Neural Information Processing Systems}, year={2023} }
Out-of-distribution Detection with Unreliable Out-of-distribution Sources
H. Zheng, Q. Wang, Z. Fang, X. Xia, F. Liu, T. Liu, and B. Han
NeurIPS 2023
@inproceedings{zheng2023unreliable, title={Out-of-distribution Detection with Unreliable Out-of-distribution Sources}, author={Haotian Zheng and Qizhou Wang and Zhen Fang and Xiaobo Xia and Feng Liu and Tongliang Liu and Bo Han}, booktitle={Advances in Neural Information Processing Systems}, year={2023} }
Out-of-distribution Detection with Implicit Outlier Transformation
Q. Wang, J. Ye, F. Liu, Q. Dai, M. Kalander, T. Liu, J. Hao, and B. Han
ICLR 2023
@inproceedings{wang2023doe, title={Out-of-distribution Detection with Implicit Outlier Transformation}, author={Qizhou Wang and Junjie Ye and Feng Liu and Quanyu Dai and Marcus Kalander and Tongliang Liu and Jianye Hao and Bo Han}, booktitle={International Conference on Learning Representations}, year={2023} }
Watermarking for Out-of-distribution Detection
Q. Wang, F. Liu, Y. Zhang, J. Zhang, C. Gong, T. Liu, and B. Han
NeurIPS 2022
@inproceedings{wang2022watermark, title={Watermarking for Out-of-distribution Detection}, author={Qizhou Wang and Feng Liu and Yonggang Zhang and Jing Zhang and Chen Gong and Tongliang Liu and Bo Han}, booktitle={Advances in Neural Information Processing Systems}, year={2022} }
Probabilistic Margins for Instance Reweighting in Adversarial Training
Q. Wang, F. Liu, B. Han, T. Liu, C. Gong, G. Niu, M. Zhou, and M. Sugiyama
NeurIPS 2021
@inproceedings{wang2021mail, title={Probabilistic Margins for Instance Reweighting in Adversarial Training}, author={Qizhou Wang and Feng Liu and Bo Han and Tongliang Liu and Chen Gong and Gang Niu and Mingyuan Zhou and Masashi Sugiyama}, booktitle={NeurIPS}, year={2021} }
Tackling Instance-dependent Label Noise via a Universal Probabilistic Model
Q. Wang, B. Han, T. Liu, G. Niu, J. Yang, and C. Gong
AAAI 2021
@inproceedings{wang2021tackling_instance, title={Tackling Instance-Dependent Label Noise via a Universal Probabilistic Model}, author={Qizhou Wang and Bo Han and Tongliang Liu and Gang Niu and Jian Yang and Chen Gong}, booktitle={AAAI}, year={2021} }
Journal
Forgetting: A New Mechanism Towards Better Large Language Model Fine-tuning
A. Taheri, A. Taban, Q. Wang, S. Ye, A. Mirzaei, T. Liu, and B. Han
TMLR, 2026
@article{taheri2026forgetting, title={Forgetting: A New Mechanism Towards Better Large Language Model Fine-tuning}, author={Ali Taheri and Alireza Taban and Qizhou Wang and Shanshan Ye and Abdolreza Mirzaei and Tongliang Liu and Bo Han}, journal={Transactions on Machine Learning Research}, year={2026} }
On the Two Facets to Conquer Wild Out-of-distribution Detection
Z. Hu, Q. Wang, X. Liu, L. Lan, and B. Han
TPAMI, 2026
@article{hu2026on, title={On the Two Facets to Conquer Wild Out-of-distribution Detection}, author={Zhaohui Hu and Qizhou Wang and Xinwang Liu and Long Lan and Bo Han}, journal={IEEE Transactions on Pattern Analysis and Machine Intelligence}, year={2026} }
W-DOE: Wasserstein Distribution-agnostic Outlier Exposure
Q. Wang, B. Han, Y. Liu, C. Gong, T. Liu, and J. Liu
TPAMI, 2025
@article{wang2025wdoe, title={W-DOE: Wasserstein Distribution-agnostic Outlier Exposure}, author={Qizhou Wang and Bo Han and Yang Liu and Chen Gong and Tongliang Liu and Jiming Liu}, journal={IEEE Transactions on Pattern Analysis and Machine Intelligence}, year={2025} }
RML++: Regroup Median Loss for Combating Label Noise
F. Li, K. Li, Q. Wang, B. Han, J. Tian, and J. Zhou
IJCV, 2025
@article{li2025rmlpp, title={RML++: Regroup Median Loss for Combating Label Noise}, author={Li, Fengpeng and Li, Kemou and Wang, Qizhou and Han, Bo and Tian, Jinyu and Zhou, Jiantao}, journal={International Journal of Computer Vision}, year={2025} }
Instance-dependent Positive and Unlabeled Learning with Labeling Bias Estimation
C. Gong, Q. Wang, T. Liu, B. Han, J. You, and D. Tao
TPAMI, 2021
@article{gong2021instance, title={Instance-dependent positive and unlabeled learning with labeling bias estimation}, author={Gong, Chen and Wang, Qizhou and Liu, Tongliang and Han, Bo and You, Jane and Yang, Jian and Tao, Dacheng}, journal={IEEE Transactions on Pattern Analysis and Machine Intelligence}, volume={44}, number={8}, pages={4163--4177}, year={2021} }
Honors & Awards
ICLR Notable Reviewer
ICLR 2025
Excellent Teaching Assistant Performance Award
HKBU 2024
ICLR Outstanding Reviewer
ICLR 2024
RPg Performance Award
HKBU 2024
Teaching Assistant Performance Award
HKBU 2023
Top Reviewer
NeurIPS 2023
RPg Performance Award
HKBU 2023
PG Day Best Presentation Award
HKBU 2023
Spotlight Paper Award
NeurIPS 2022
Outstanding Reviewer
ICML 2022
RPg Performance Award
HKBU 2022
Outstanding Reviewer
ICML 2021
Outstanding Undergraduate Thesis
NJUST 2021
Academic Service & Teaching

Service

  • Area Chair: NeurIPS (2026, Position Paper Track)
  • Editorial Board Member: MLJ (2026 - Now)
  • Conference Reviewer / PC Member: ICML, NeurIPS, ICLR, UAI, CVPR
  • Journal Reviewer: TPAMI, IJCV, TNNLS, NN, TMLR

Teaching Assistant

  • COMP1016 (G) Mathematical Methods for Business Computing
  • COMP7250 (G) Machine Learning
  • COMP3075 (UG) Introduction to AI and Machine Learning
  • COMP1006 (G) Facets of Computing
  • COMP7870 (G) IT Innovation Management and Entrepreneurship
Presentations
2026

On the Insights and Strategies for OOD Detection Learning

AAAI Tutorial and Lab Forum · Slide

2025

LLM Unlearning: Methodologies, Evaluations, and Broader Applications

Shanghai Jiao Tong University · Slide

Research Mentorship
Yue Wang
UCL UG → ICML '25, ICLR '26 →
UniMelb PhD, 2026
Ali Taheri
IUT UG → TMLR '26 →
MPI PhD, 2026
Alireza Taban
IUT UG → TMLR '26 →
UWaterloo PhD, 2026
Puning Yang
UCAS Master → ICLR '25, ICML '25 →
MBZUAI PhD, 2025
Haotian Zheng
XDU UG → NeurIPS '23 →
HKU PhD, 2024