Research

Book Chapter

1. Data-Driven Approaches for Detecting and Identifying Anomalous Data Streams
   S. Zou, Y. Liang, H. V. Poor, X. Shi
   Signal Processing and Machine Learning for Biomedical Big Data, edited by Ervin Sejdic and Tiago Falk, CRC Press, 2018.

2. A Broadcast Approach to Fading Channels under Secrecy Constraints
   S. Zou, Y. Liang, L. Lai, H. V. Poor, S. Shamai
   Information-Theoretic Perspectives on 5G Systems and Beyond, Edited by Ivana Maric, Osvaldo Simeone, Shlomo Shamai (Shitz), Cambridge University Press, 2017.

Journal Publications

1. Independently-Normalized SGD for Generalized-Smooth Nonconvex Optimization

Y Yang, E Tripp, Y Sun, S Zou, Y Zhou
TMLR, 2025

2. Theoretical Study of Conflict-Avoidant Multi-Objective Reinforcement Learning
   Yudan Wang, Peiyao Xiao, Hao Ban, Kaiyi Ji, Shaofeng Zou
   IEEE Transactions on Information Theory, 2025

3. Understanding Information Disclosure from Secure Computation Output: A Comprehensive Study of Average Salary Computation
   Alessandro Baccarini, Marina Blanton, Shaofeng Zou
   ACM Transactions on Privacy and Security, 2024

4. Convergence Guarantees for RMSProp and Adam in Generalized-smooth Non-convex Optimization with Affine Noise Variance
   Qi Zhang, Yi Zhou, Shaofeng Zou
   TMLR, 2025

5. Achieving the Asymptotically Minimax Optimal Sample Complexity of Offline Reinforcement Learning: A DRO-Based Approach
   Yue Wang, Jinjun Xiong, Shaofeng Zou
   Transactions on Machine Learning Research, 2024.

6. Faster Algorithm and Sharper Analysis for Constrained Markov Decision Process
   Tianjiao Li, Ziwei Guan, Shaofeng Zou, Tengyu Xu, Yingbin Liang, Guanghui Lan
   Operations Research Letters, 2024

7. Quickest Change Detection in Autoregressive Models
   Zhongchang Sun, Shaofeng Zou
   IEEE Transactions on Information Theory, 2024

8. Finite-Time Error Bounds for Greedy-GQ
   Y. Wang, Y. Zhou, S. Zou
   Machine Learning, 2024

9. Robust Average-Reward Reinforcement Learning
   Y. Wang, A. Velasquez, G. Atia, A. Prater-Bennette, S. Zou
   Journal of Artificial Intelligence Research, 2024.

10. What is the Solution for State-Adversarial Multi-Agent Reinforcement Learning?
    S. Han, S. Su, S. He, S. Han, H. Yang, S. Zou, F. Miao
    Transactions on Machine Learning Research, 2024.

11. Decentralized Robust V-learning for Solving Markov Games with Model Uncertainty
    Shaocong Ma, Ziyi Chen, Shaofeng Zou, and Yi Zhou
    Journal of Machine Learning Research, 2023.

12. Data-Driven Quickest Change Detection in (Hidden) Markov Models
    Qi Zhang, Zhongchang Sun, Luis Herrera, Shaofeng Zou
    IEEE Transactions on Signal Processing, 2024.

13. Provably Efficient Offline Reinforcement Learning with Trajectory-Wise Reward
    T. Xu, Y. Wang, S. Zou, Y. Liang
    IEEE Transactions on Information Theory, 2024.

14. Robust Multi-Agent Reinforcement Learning with State Uncertainty
    Sihong He, Songyang Han, Sanbao Su, Shuo Han, Shaofeng Zou, Fei Miao
    Transactions on Machine Learning Research, 2023.

15. A Probabilistic Approach to Series Arc Fault Detection and Identification in DC Microgrids
    K. Gajula, V. Le, X. Yao, S. Zou, L. Herrera
    IEEE Journal of Emerging and Selected Topics in Industrial Electronics, 2023.

16. Kernel Robust Hypothesis Testing
    Z. Sun, S. Zou
    IEEE Transactions on Information Theory, 2023.

17. Quickest Anomaly Detection in Sensor Networks With Unlabeled Samples
    Z. Sun, S. Zou
    IEEE Transactions on Signal Processing, 2023.

18. Adversarially robust sequential hypothesis testing
    S. Cao, R. Zhang, S. Zou
    Sequential Analysis, 2022.

19. Quickest Change Detection in Anonymous Heterogeneous Sensor Networks
    Z. Sun, S. Zou, R. Zhang, Q. Li
    IEEE Transactions on Signal Processing, 2022.

20. Population Risk Improvement with Model Compression: An Information-Theoretic Approach
    Y. Bu, W. Gao, S. Zou, and V. V. Veeravalli
    Entropy, Sept. 2021.

21. Sequential Change Detection: Classical Results and New Directions
    L. Xie, S. Zou, Y. Xie, V. V. Veeravalli
    IEEE Journal on Selected Areas in Information Theory, 2021.

22. Tightening Mutual Information Based Bounds on Generalization Error
    Y. Bu, S. Zou, V. V. Veeravalli
    IEEE Journal on Selected Areas in Information Theory, May 2020.

23. Sequential Algorithms for Moving Anomaly Detection in Networks
    G. Rovatsos, S. Zou, V. V. Veeravalli
    Sequential Analysis, 2020.

24. Quickest Detection of Dynamic Events in Networks
    S. Zou, V. V. Veeravalli, J. Li, D. Towsley
    IEEE Transactions on Information Theory, 2020.

25. Linear-Complexity Exponentially-Consistent Tests for Universal Outlying Sequence Detection
    Y. Bu, S. Zou, V. V. Veeravalli
    IEEE Transactions on Signal Processing, vol. 67, no. 8, pp. 2115-2128, April 15, 2019.

26. Quickest Change Detection under Transient Dynamics: Theory and Asymptotic Analysis
    S. Zou, G. Fellouris, V. V. Veeravalli
    IEEE Transactions on Information Theory, vol. 65, no. 3, pp. 1397-1412, March 2019.

27. Estimation of KL Divergence: Optimal Minimax Rate
    Y. Bu*, S. Zou*, Y. Liang, V. V. Veeravalli
    IEEE Transactions on Information Theory, vol. 64, no. 4, pp. 2648-2674, April 2018. (Bu and Zou contributed equally).

28. Degraded Broadcast Channel with Secrecy Outside a Bounded Range
    S. Zou, Y. Liang, L. Lai, H. V. Poor, S. Shamai (Shitz)
    IEEE Transactions on Information Theory, vol. 64, no. 3, pp. 2104-2120, Mar. 2018.

29. Nonparametric Detection of Anomalous Data Streams
    S. Zou, Y. Liang, H. V. Poor, X. Shi
    IEEE Transactions on Signal Processing, vol. 65, no. 21, pp. 5785-5797, Nov. 2017.

30. Nonparametric Detection of Geometric Structures over Networks
    S. Zou, Y. Liang, H. V. Poor
    IEEE Transactions on Signal Processing, vol. 65, no. 19, pp. 5034-5046, Oct. 2017.

31. Broadcast Networks with Layered Decoding and Layered Secrecy: Theory and Applications
    S. Zou, Y. Liang, L. Lai, H. V. Poor, S. Shamai (Shitz)
    Proceedings of the IEEE, vol.103, no.10, pp.1841-1856, Oct. 2015.

32. An Information Theoretic Approach to Secret Sharing
    S. Zou, Y. Liang, L. Lai, S. Shamai (Shitz)
    IEEE Transactions on Information Theory, vol.61, no.6, pp.3121-3136, June 2015.

Conference and Workshop Publications

2025

• Near-Optimal Sample Complexity for Iterated CVaR Reinforcement Learning with a Generative Model
  Zilong Deng, Simon Khan, Shaofeng Zou
  The 28th International Conference on Artificial Intelligence and Statistics (AISTATS), 2025  (acceptance rate: 31.3%)

• MGDA Converges under Generalized Smoothness, Provably
  Qi Zhang, Peiyao Xiao, Shaofeng Zou, Kaiyi Ji
  The Thirteenth International Conference on Learning Representations (ICLR), 2025 (acceptance rate: 32.08%)

• Revisiting Large-Scale Non-convex Distributionally Robust Optimization
  Qi Zhang, Yi Zhou, Simon Khan, Ashley Prater-Bennette, Lixin Shen, Shaofeng Zou
  The Thirteenth International Conference on Learning Representations (ICLR), 2025 (acceptance rate: 32.08%)

2024

• A Unified Principle of Pessimism for Offline Reinforcement Learning under Model Mismatch
  Yue Wang, Zhongchang Sun, Shaofeng Zou
  Conference on Neural Information Processing Systems (NeurIPS), Vancouver CA, Dec. 2024 (acceptance rate: 25.8%)

• Policy Optimization for Robust Average Reward MDPs
  Zhongchang Sun, Sihong He, Fei Miao, Shaofeng Zou
  Conference on Neural Information Processing Systems (NeurIPS), Vancouver CA, Dec. 2024 (acceptance rate: 25.8%)

• Non-Asymptotic Analysis for Single-Loop (Natural) Actor-Critic with Compatible Function Approximation
  Yudan Wang, Yue Wang, Yi ZHou, Shaofeng Zou
  International Conference on Machine Learning (ICML), 2024 (acceptance rate: 27.5%)

• Constrained Reinforcement Learning Under Model Mismatch
  Zhongchang Sun, Sihong He, Fei Miao, Shaofeng Zou
  International Conference on Machine Learning (ICML), 2024 (acceptance rate: 27.5%)

• Model-Free Robust Reinforcement Learning with Sample Complexity Analysis
  Yudan Wang, Shaofeng Zou, Yue Wang
  Conference on Uncertainty in Artificial Intelligence (UAI 2024). (acceptance rate: 27%)

• Robust Multi-Hypothesis Testing with Moment-Constrained Uncertainty Sets
  Akshayaa Magesh, Zhongchang Sun, Venugopal Veeravalli, Shaofeng Zou
  IEEE International Symposium on Information Theory, 2024

• Understanding Information Disclosure from Secure Computation Output: A Study of Average Salary Computation
  Alessandro Baccarini, Marina Blanton, Shaofeng Zou
  ACM Conference on Data and Application Security and Privacy (CODASPY) (21.25% acceptance rate)

• Sample Complexity Characterization for Linear Contextual MDPs
  Junze Deng, Yuan Cheng, Shaofeng Zou, Yingbin Liang
  International Conference on Artificial Intelligence and Statistics (AISTATS) 2024 (acceptance rate: 27.6%)

• Large-scale Non-convex Stochastic Constrained Distributionally Robust Optimization
  Qi Zhang, Yi Zhou, Ashley Prater-Bennette, Lixin Shen, Shaofeng Zou
  AAAI Conference on Artificial Intelligence (AAAI), 2024 (acceptance rate: 23.75%)

2023

• Large-scale Non-convex Stochastic Constrained Distributionally Robust Optimization
  Qi Zhang, Yi Zhou, Ashley Prater-Bennette, Lixin Shen, Shaofeng Zou
  NeurIPS workshop: Optimization for Machine Learning, 2023

• A Robust and Constrained Multi-Agent Reinforcement Learning Electric Vehicle Rebalancing Method in AMoD Systems
  Sihong He, Yue Wang, Shuo Han, Shaofeng Zou, Fei Miao
  IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2023

• Model-Free Robust Average-Reward Reinforcement Learning
  Y. Wang, A. Velasquez, G. Atia, A. Prater-Bennette, S. Zou
  International Conference on Machine Learning (ICML), 2023 (acceptance rate: 27.9%)

• Data-Driven Quickest Change Detection in Hidden Markov Models
  Q. Zhang, Z. Sun, L. Herrera, S. Zou
  IEEE International Symposium on Information Theory (ISIT), 2023

• Robust Multi-Agent Reinforcement Learning Considering State Uncertainties
  Sihong He, Songyang Han, Sanbao Su, Shuo Han, Shaofeng Zou, Fei Miao
  AI4ABM Workshop at the International Conference on Learning Representations (ICLR), 2023

• A Robust and Constrained Multi-Agent Reinforcement Learning Method for Electric Vehicle AMoD Systems
  Sihong He, Yue Wang, Shuo Han, Shaofeng Zou, Fei Miao
  AI4ABM Workshop at the International Conference on Learning Representations (ICLR), 2023

• Data-Driven Quickest Change Detection in Markov Models
  Q. Zhang, Z. Sun, L. Herrera, S. Zou
  IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2023.

• ROBUST HYPOTHESIS TESTING WITH MOMENT CONSTRAINED UNCERTAINTY SETS
  A. Magesh, Z. Sun, V. Veeravalli, S. Zou (Magesh and Sun contribute equally)
  IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2023.

• Robust Average-Reward Markov Decision Processes
  Y. Wang, A. Velasquez, G. Atia, A. Prater-Bennette, S. Zou
  Thirty-Seventh AAAI Conference on Artificial Intelligence (AAAI), 2023 (Oral, acceptance rate: 19.6%)
  Distinguished Paper Award  out of 1,721 accepted papers!

2022

• Data-Driven Robust Multi-Agent Reinforcement Learning
  Y. Wang, Y. Wang, Y. Zhou, A. Velasquez, S. Zou
  IEEE International Workshop on MACHINE LEARNING FOR SIGNAL PROCESSING (MLSP), 2022

• Policy Gradient Method For Robust Reinforcement Learning
  Y. Wang, S. Zou
  International Conference on Machine Learning (ICML), 2022 (acceptance rate: 21.9%)
  slides

• Sample and Communication-Efficient Decentralized Actor-Critic Algorithms with Finite-Time Analysis
  Z. Chen, Y. Zhou, R. Chen, S. Zou
  International Conference on Machine Learning (ICML), 2022 (acceptance rate: 21.9%)

• Robust Hypothesis Testing With Kernel Uncertainty Sets
  Z. Sun, S. Zou
  IEEE International Symposium on Information Theory (ISIT), 2022

2021

• Online Robust Reinforcement Learning with Model Uncertainty
  Y. Wang, S. Zou
  Conference on Neural Information Processing Systems (NeurIPS), Virtual, Dec 2021. (acceptance rate: 26%)

• Non-Asymptotic Analysis for Two Time-scale TDC with General Smooth Function Approximation
  Y. Wang, S. Zou, Y. Zhou
  Conference on Neural Information Processing Systems (NeurIPS), Virtual, Dec 2021. (acceptance rate: 26%)

• Quickest Detection of Series Arc Faults on DC Microgrids
  K. Gajula, V. Le, X. Yao, S. Zou, L. Herrera
  IEEE Energy Conversion Congress and Exposition (ECCE), 2021

• A Data-Driven Approach to Robust Hypothesis Testing Using Kernel MMD Uncertainty Sets
  Z. Sun, S. Zou
  IEEE International Symposium on Information Theory (ISIT), 2021

• Quickest Dynamic Anomaly Detection in Anonymous Heterogeneous Sensor Networks
  Z. Sun, S. Zou
  IEEE International Symposium on Information Theory (ISIT), 2021

• A Computationally Efficient Algorithm for Quickest Change Detection in Anonymous Heterogeneous Sensor Networks
  Z. Sun, Q. Li, R. Zhang, S. Zou
  IEEE International Symposium on Information Theory (ISIT), 2021

• Greedy-GQ with Variance Reduction: Finite-time Analysis and Improved Complexity
  S. Ma, Y. Zhou, S. Zou
  International Conference on Learning Representations (ICLR) 2021 (acceptance rate: 28.7%)

• Learning Graph Neural Networks with Approximate Gradient Descent
  Q. Li, S. Zou, W. Zhong
  AAAI Conference on Artificial Intelligence (AAAI), Virtual Conference, Feb. 2021 (acceptance rate: 21%)

2020

• Variance-Reduced Off-Policy TDC Learning: Non-Asymptotic Convergence Analysis
  S. Ma, Y. Zhou, S. Zou
  Conference on Neural Information Processing Systems (NeurIPS), Vancouver CA, Dec 2020. (acceptance rate: 20.1%)

• Finite-sample Analysis of Greedy-GQ with Linear Function Approximation under Markovian Noise
  Y. Wang, S. Zou
  Conference on Uncertainty in Artificial Intelligence (UAI), Aug. 2020 (acceptance rate: 27.6%)

• A Game-Theoretic Approach to Sequential Detection in Adversarial Environments
  R. Zhang, S. Zou
  IEEE International Symposium on Information Theory (ISIT), June 2020.

• Quickest Change Detection in Anonymous Heterogeneous Sensor Networks
  Z. Sun, S. Zou, Q. Li
  IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Barcelona, Spain, May. 2020.

• Information-Theoretic Understanding of Population Risk Improvement with Model Compression
  Y. Bu, W. Gao, S. Zou, V. V. Veeravalli
  AAAI Conference on Artificial Intelligence (AAAI), New York, USA, Feb. 2020 (acceptance rate: 20.6%)
  Poster

2019

• Finite-Sample Analysis for SARSA with Linear Function Approximation
  S. Zou, T. Xu, Y. Liang
  Conference on Neural Information Processing Systems (NeurIPS), Vancouver CA, Dec 2019. (acceptance rate: 21%)
  Poster
  Slides

• Two Time-scale Off-Policy TD Learning: Non-asymptotic Analysis over Markovian Samples
  T. Xu, S. Zou, Y. Liang
  Conference on Neural Information Processing Systems (NeurIPS), Vancouver CA, Dec 2019. (acceptance rate: 21%)
  Poster

• A Consensus-based Approach for Distributed Quickest Detection of Significant Events in Networks
  J. Li, D. Towsley, S. Zou, V. V. Veeravalli and G. Ciocarlie
  Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, CA, USA, 2019.

• Tightening Mutual Information Based Bounds on Generalization Error
  Y. Bu, S. Zou, V. V. Veeravalli
  IEEE International Symposium on Information Theory (ISIT), June 2019.

• Quickest Detection of a Moving Target in a Sensor Network
  G. Rovatsos, S. Zou, V. V. Veeravalli
  IEEE International Symposium on Information Theory (ISIT), June 2019.

• Distributed Quickest Detection of Significant Events in Networks
  S. Zou, V. V. Veeravalli, J. Li, D. Towsley, A. Swami
  IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 2019.

2018

• Quickest Detection of Significant Events in Structured Networks
  S. Zou, V. V. Veeravalli, J. Li, D. Towsley
  Asilomar Conference on Signals, Systems, and Computers, Oct. 2018.

• Stochastic Control of Power Supply in Data Centers
  G. Rovatsos, S. Zou, A. Dominguez-Garcia, V. V. Veeravalli
  Asilomar Conference on Signals, Systems, and Computers, Oct. 2018.

• Quickest Detection of Dynamic Events in Sensor Networks
  S. Zou, V. V. Veeravalli
  IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Alberta, Canada, April. 2018.

2017

• Gaussian Fading Channel with Secrecy Outside a Bounded Range
  S. Zou, Y. Liang, S. Shamai
  IEEE Conference on Communications and Network Security (CNS): The Workshop on Physical-Layer Methods for Wireless Security, Las Vegas, USA Oct. 2017.

• Asymptotic Optimality of D-CuSum for Quickest Change Detection under Transient Dynamics
  S. Zou, G. Fellouris, V. V. Veeravalli
  IEEE International Symposium on Information Theory (ISIT), Aachen, Germany, June 2017.

• Linear-Complexity Exponentially-Consistent Tests for Universal Outlying Sequence Detection
  Y. Bu, S. Zou, V. V. Veeravalli
  IEEE International Symposium on Information Theory (ISIT), Aachen, Germany, June 2017.

• Quickest Change Detection under Transient Dynamics
  G. Rovatsos, S. Zou, V. V. Veeravalli
  IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), New Orleans, USA, Mar. 2017.

2016

• K-User Degraded Broadcast Channel with Secrecy Outside a Bounded Range
  S. Zou, Y. Liang, L. Lai, H. V. Poor, S. Shamai (Shitz)
  IEEE Information Theory Workshop (ITW), Cambridge, Sept. 2016.

• Estimation of KL Divergence Between Large-Alphabet Distributions
  Y. Bu, S. Zou, Y. Liang, V. V. Veeravalli
  IEEE International Symposium on Information Theory (ISIT), Barcelona, Jul. 2016.

• Universal Outlying Sequence Detection for Continuous Observations
  Y. Bu, S. Zou, Y. Liang, V. V. Veeravalli
  IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Shanghai, Mar. 2016.

• Nonparametric Detection of an Anomalous Disk over a Two-Dimensional Lattice Network
  S. Zou, Y. Liang, H. V. Poor
  IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Shanghai, Mar. 2016.

• Recent Results on Broadcast Networks with Layered Decoding and Secrecy: an Overview
  S. Zou, Y. Liang, L. Lai, H. V. Poor, S. Shamai (Shitz)
  International Zurich Seminar on Communications (IZS), Zurich, Mar. 2016.

2015

• Rate Splitting and Sharing for Degraded Broadcast Channel with Secrecy Outside a Bounded Range
  S. Zou, Y. Liang, L. Lai, S. Shamai (Shitz)
  IEEE International Symposium on Information Theory (ISIT), Hongkong, Jun. 2015.

• Degraded Broadcast Channel: Secrecy Outside of a Bounded Range
  S. Zou, Y. Liang, L. Lai, S. Shamai (Shitz)
  IEEE Information Theory Workshop (ITW), Jerusalem, Apr. 2015.

2014

• Unsupervised Nonparametric Anomaly Detection: A Kernel Method
  S. Zou, Y. Liang, H. V. Poor, X. Shi
  52th Annual Allerton Conference on Communication, Control, and Computing, Monticello, IL, Oct. 2014.

• A Kernel-Based Nonparametric Test for Anomaly Detection over Line Network
  S. Zou, Y. Liang, H. V. Poor
  IEEE International Workshop on Machine Learning for Signal Processing (MLSP), Reims, Sept. 2014.

• Kernel-Based Nonparametric Anomaly Detection
  S. Zou, Y. Liang, H. V. Poor, X. Shi
  IEEE 15th Workshop on Signal Processing Advances in Wireless Communications (SPAWC), Toronto, Jun. 2014.

• Layered Decoding and Secrecy over Degraded Gaussian MIMO Broadcast Channels and Application in Secret Sharing
  S. Zou, Y. Liang, L. Lai, S. Shamai (Shitz)
  IEEE International Symposium on Information Theory (ISIT), Honolulu, Jun. 2014.

2013

• Layered Decoding and Secrecy over Degraded Broadcast Channels
  S. Zou, Y. Liang, L. Lai, S. Shamai (Shitz)
  IEEE 14th Workshop on Signal Processing Advances in Wireless Communications (SPAWC), Darmstadt, Jun. 2013.

• Multiple Access Channel with State Uncertainty at Transmitters
  S. Zou, Y. Liang, S. Shamai (Shitz)
  IEEE International Symposium on Information Theory (ISIT), Istanbul, Jun. 2013.

Technical Reports

1. Robust Constrained Reinforcement Learning
   Y. Wang, F. Miao, S. Zou
   preprints available at Arxiv

Acknowledgement

Our research is generously supported by NSF, DARPA, Arizona State University and University at Buffalo.