Ziping Zhao

Preprints

• Robust M-Estimation of Location: Non-convex Optimization Landscape Analysis and Algorithms
  Hongyuan Yang, Ying Sun, Ziping Zhao. Short version at ITW 2024.

• High-dimensional Graphical Models
  Fengpei Li, Ziping Zhao. Short version at ISIT 2024.

• Discerning and Enhancing the Weighted Sum-Rate Maximization Algorithms [Arxiv]
  Zepeng Zhang, Ziping Zhao, Kaiming Shen, Daniel P. Palomar, Wei Yu. Short version at ICASSP 2023.

• Towards Understanding Graph Neural Networks: An Algorithm Unrolling Perspective [Arxiv]
  Zepeng Zhang, Ziping Zhao. Short version at DLG 2022.
  

• Rate Maximizations for RIS-Aided Wireless Networks: A Unified Framework via Block Minorization-Maximization [Arxiv]
  Zepeng Zhang, Ziping Zhao. Short version received Best Student Paper Award Finalist at SPAWC 2021.
  

• ML Estimation of the Generalized Gaussian Distribution with Applications to GARCH Models
  Chenyu Gao, Ziping Zhao. Short version at SSP 2021.
  

Journal Papers

• High-Dimensional Huber Regression over Networks
  Wenfu Xia, Quan Wei, Ziping Zhao,
  IEEE Transactions on Signal Processing (TSP), July 2026. Short version received Best Student Paper Award Finalist at SAM 2024.
  

• MM-Net: Recurrent Unfolding with Adaptive Majorization for Weighted Sum-Rate Beamforming
  Zhexian Yang, Zepeng Zhang, Ziping Zhao,
  IEEE Signal Processing Letters (SPL), June 2026.
  

• Factor-Based Large Covariance Matrix Estimation: Nonconvex Optimization and Statistical Guarantees
  Shanshan Zou, Ziping Zhao,
  IEEE Transactions on Signal Processing (TSP), October 2025. Short version at ICASSP 2024.
  

• Maximum Likelihood Estimation of Gaussian and Student's GARCH: A Unified Penalty Method
  Chenyu Gao, Ziping Zhao, Daniel P. Palomar,
  IEEE Transactions on Signal Processing (TSP), vol. 73, pp. 4840-4855, August 2025. Short version at SSP 2023.
  

• Graph Neural Networks With Adaptive Structures
  Zepeng Zhang, Songtao Lu, Zengfeng Huang, Ziping Zhao,
  IEEE Journal of Selected Topics in Signal Processing (JSTSP), vol. 19, no. 1, pp. 181-194, October 2024. Short version at GSP 2024.
  

• Accelerating Quadratic Transform and WMMSE
  Kaiming Shen, Ziping Zhao, Yannan Chen, Zepeng Zhang, Hei Victor Cheng,
  IEEE Journal on Selected Areas in Communications (JSAC), vol. 42, no. 11, pp. 3110-3124, July 2024. Short version at ISIT 2024. Featured Article
  

• Large Covariance Matrix Estimation With Oracle Statistical Rate via Majorization-Minimization [errata]
  Quan Wei, Ziping Zhao,
  IEEE Transactions on Signal Processing (TSP), vol. 71, pp. 3328-3342, September 2023. Short version received Best Student Paper Award at ICASSP 2023.
  

• Optimal Mean-Reverting Portfolio With Leverage Constraint for Statistical Arbitrage in Finance
  Ziping Zhao, Rui Zhou, Daniel P. Palomar,
  IEEE Transactions on Signal Processing (TSP), vol. 67, no. 7, pp. 1681-1695, April 2019. Short version at SSP 2018.
  

• Mean-Reverting Portfolio with Budget Constraint
  Ziping Zhao, Daniel P. Palomar,
  IEEE Transactions on Signal Processing (TSP), vol. 66, no. 9, pp. 2342-2357, May 2018. Short version at Asilomar 2016.
  

Conference Papers in Machine Learning

• Inference from Quantized Data via Normal Variance-Mean Mixtures
  Chenyu Gao, Zhexian Yang, Ziping Zhao,
  International Conference on Machine Learning (ICML), Seoul, South Korea, July 6-11, 2026.
  

• Positive Definite Sparse Covariance Estimation via Dual Space Optimization
  Fengpei Li*, Wenfu Xia*, Ziping Zhao, (* = eq. contr.)
  Annual AAAI Conference on Artificial Intelligence (AAAI), Singapore, January 20–27, 2026.
  Oral Paper

• High-Dimensional Tensor Regression with Oracle Properties
  Wenbin Wang, Yu Shi, Ziping Zhao,
  International Conference on Machine Learning (ICML), Vancouver, BC, Canada, July 13-19, 2025.
  

• Covariance Selection over Networks (Sparse Inverse Covariance Matrix Estimation over Networks)
  Wenfu Xia, Fengpei Li, Ying Sun, Ziping Zhao,
  International Conference on Artificial Intelligence and Statistics (AISTATS), Mai Khao, Thailand, May 3-5, 2025.
  

• Large Covariance Matrix Estimation With Nonnegative Correlations
  Yixin Yan, Qiao Bill Yang, Ziping Zhao,
  International Conference on Artificial Intelligence and Statistics (AISTATS), Mai Khao, Thailand, May 3-5, 2025.
  

• Designing Graph Neural Networks via Algorithm Unrolling
  Zepeng Zhang, Ziping Zhao,
  International KDD Workshop on Deep Learning on Graphs: Methods and Applications, Washington DC Convention Center, USA, August 14-18, 2022.
  

Conference Papers in Signal Processing

• Weighted Sum Secrecy Rate Maximization via Minorization-Maximization
  Zhexian Yang, Zepeng Zhang, Ziping Zhao,
  IEEE International Symposium on Information Theory (ISIT), Guangzhou, China, June 28-July 03, 2026.
  

• From WMMSE to XMMSE: An Old Melody Sung in a Fast New Tune
  Zhexian Yang, Ziping Zhao,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Barcelona, Spain, May 4-8, 2026.
  Best Student Paper Award candidate (Signal Processing for Communications and Networking Track)

• Large Sparse Covariance Matrix Estimation via Dual Proximal Gradient Method
  Fengpei Li, Ziping Zhao,
  Asia-Pacific Signal and Information Processing Conference, Singapore, Oct. 22-24, 2025.
  

• Noisy Bilinear Low-Rank Matrix Sketching
  Wenbin Wang, Xindi Ping, Cheng Cheng, Ziping Zhao,
  IEEE Information Theory Workshop (ITW), Sydney, Australia, Sept. 29- Oct. 3, 2025.
  

• Weighted Sum-Rate Maximization for Beamforming Design Using Minorization-Maximization: Convergence Rate and Deep Unfolding
  Zhexian Yang, Zepeng Zhang, Ziping Zhao,
  European Signal Processing Conference (EUSIPCO), Isola delle Femmine-Palermo, Italy, Sept. 8-12, 2025.
  

• Mutual Information Maximization for Waveform Design Using Minorization-Maximization
  Zhexian Yang, Linlong Wu, Ziping Zhao,
  European Signal Processing Conference (EUSIPCO), Isola delle Femmine-Palermo, Italy, Sept. 8-12, 2025.
  

• Optimal Compressive Covariance Sketching via Rank-One Sampling
  Wenbin Wang, Ziping Zhao,
  International Conference on Sampling Theory and Applications (SampTA), Vienna, Austria, July 28-August 1, 2025.
  

• Achieving Oracle Rate for Large Covariance Matrix Estimation From Quadratic Measurements
  Wenbin Wang, Ziping Zhao,
  IEEE International Symposium on Information Theory (ISIT), Ann Arbor, USA, June 22-27, 2025.
  

• Beyond Jensen's Inequality: Speeding Up ML Estimation of Generalized Hyperbolic Distributions
  Chenyu Gao, Ziping Zhao,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Hyderabad, India, April 6-11, 2025.
  

• Sparse PCA with Oracle Rate in High Dimensions
  Wenfu Zhong, Ziping Zhao,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Hyderabad, India, April 6-11, 2025.
  

• Large Covariance Matrix Estimation for Groups of Highly Correlated Variables via Nonconvex Optimization
  Shanshan Zou, Ziping Zhao,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Hyderabad, India, April 6-11, 2025.
  

• A Joint Graph Signal and Laplacian Denoising Network Inspired by Majorization-Minimization
  Zepeng Zhang, Ziping Zhao,
  Asia-Pacific Signal and Information Processing Conference, Macau, China, Dec. 3-6, 2024.
  

• Sparse Blind Deconvolution and Demixing via Block Majorization-Minimization
  Mengting Chen, Ziping Zhao,
  Asia-Pacific Signal and Information Processing Conference, Macau, China, Dec. 3-6, 2024.
  

• Geometric Analysis of Non-convex Optimization Landscapes for Robust M-Estimation of Location
  Hongyuan Yang, Ziping Zhao, Ying Sun,
  IEEE Information Theory Workshop (ITW), Shenzhen, China, Nov. 24-28, 2024.
  

• Improved Stability Bounds for Graph Convolutional Neural Networks under Graph Perturbations
  Jun Zhang, Ziping Zhao,
  IEEE Information Theory Workshop (ITW), Shenzhen, China, Nov. 24-28, 2024.
  

• Two-way Sparse Reduced-Rank Regression via Scaled Gradient Descent with Hard Thresholding
  Cheng Cheng, Ziping Zhao,
  IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM), Corvallis, OR, USA, July 8-11, 2024.
  

• Distributed Sparse Covariance Matrix Estimation
  Wenfu Xia, Ziping Zhao, Ying Sun,
  IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM), Corvallis, OR, USA, July 8-11, 2024.
  

• High-Dimensional Constrained Huber Regression
  Quan Wei, Ziping Zhao,
  IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM), Corvallis, OR, USA, July 8-11, 2024.
  Best Student Paper Award Finalist

• Guaranteed Robust Large Precision Matrix Estimation Under -distribution
  Fengpei Li, Ziping Zhao,
  IEEE International Symposium on Information Theory (ISIT), Athens, Greece, July 7-12, 2024.
  

• Efficient Nonconvex Optimization for Two-way Sparse Reduced-Rank Regression
  Cheng Cheng, Ziping Zhao,
  IEEE International Symposium on Information Theory (ISIT), Athens, Greece, July 7-12, 2024.
  

• Accelerating Quadratic Transform and WMMSE
  Kaiming Shen, Ziping Zhao, Yannan Chen, Zepeng Zhang, Hei Victor Cheng,
  IEEE International Symposium on Information Theory (ISIT), Athens, Greece, July 7-12, 2024.
  

• On Stability of GCNN Under Graph Perturbations
  Jun Zhang, Ziping Zhao,
  Graph Signal Processing Workshop (GSP), Delft, Netherlands, June 24-26, 2024.
  

• Graph Neural Networks With Adaptive Structures
  Zepeng Zhang, Songtao Lu, Zengfeng Huang, Ziping Zhao,
  Graph Signal Processing Workshop (GSP), Delft, Netherlands, June 24-26, 2024.
  

• Large Covariance Matrix Estimation Based on Factor Models via Nonconvex Optimization
  Shanshan Zou, Ziping Zhao,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Seoul, Korea, April 14-19, 2024.
  

• Accelerating Gradient Descent for Over-parameterized Asymmetric Low-rank Matrix Sensing via Preconditioning
  Cheng Cheng, Ziping Zhao,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Seoul, Korea, April 14-19, 2024.
  

• Joint Blind Deconvolution and Demixing of Sparse Signals via Factorization and Nonconvex Optimization
  Mengting Chen, Ziping Zhao,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Seoul, Korea, April 14-19, 2024.
  

• Efficient Sparse Reduced-Rank Regression With Covariance Estimation
  Fengpei Li, Ziping Zhao,
  IEEE Statistical Signal Processing Workshop (SSP), Hanoi, Vietnam, July 2-5, 2023.
  

• C-ISTA: Iterative Shrinkage-Thresholding Algorithm for Sparse Covariance Matrix Estimation
  Wenfu Xia, Ziping Zhao, Ying Sun,
  IEEE Statistical Signal Processing Workshop (SSP), Hanoi, Vietnam, July 2-5, 2023.
  

• A Novel Algorithm for GARCH Model Estimation
  Chenyu Gao, Ziping Zhao, Daniel P. Palomar,
  IEEE Statistical Signal Processing Workshop (SSP), Hanoi, Vietnam, July 2-5, 2023.
  

• Large Covariance Matrix Estimation With Oracle Statistical Rate
  Quan Wei, Ziping Zhao,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Rhodes Island, Greece, June 4-10, 2023.
  Best Student Paper Award (Signal Processing Theory and Methods Track), Top 3% Paper

• Enhancing the Efficiency of WMMSE and FP for Beamforming by Minorization-Maximization
  Zepeng Zhang, Ziping Zhao, Kaiming Shen,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Rhodes Island, Greece, June 4-10, 2023.
  Top 3% Paper

• Sparse Reduced-Rank Regression With Adaptive Selection of Groups of Predictors
  Quan Wei, Yujia Zhang, Ziping Zhao,
  Annual Asilomar Conference on Signals, Systems, and Computers (Asilomar), Pacific Grove, CA, USA, Oct. 31st - Nov. 3rd, 2021.
  

• Multi-Period Portfolio Optimization for Index Tracking in Finance
  Xiuyuan Huang, Zepeng Zhang, Ziping Zhao,
  Annual Asilomar Conference on Signals, Systems, and Computers (Asilomar), Pacific Grove, CA, USA, Oct. 31st - Nov. 3rd, 2021.
  

• Weighted Sum-Rate Maximization for Multi-Hop RIS-Aided Multi-User Communications: A Minorization-Maximization Approach
  Zepeng Zhang, Ziping Zhao,
  IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), Lucca, Italy, Sep. 27‐30, 2021.
  Best Student Paper Award Finalist

• Joint Design of Transmit Waveforms and Reveive Filters for MIMO Radar via Manifold Optimization
  Huanyu Zhang, Ziping Zhao,
  European Signal Processing Conference (EUSIPCO), Dublin, Ireland, Aug. 23-27, 2021.
  

• Vast Portfolio Selection With Submodular Norm Regularization
  Zepeng Zhang, Ziping Zhao,
  European Signal Processing Conference (EUSIPCO), Dublin, Ireland, Aug. 23-27, 2021.
  

• Scalable Financial Index Tracking With Graph Neural Networks
  Zepeng Zhang, Ziping Zhao,
  IEEE Statistical Signal Processing Workshop (SSP), Rio de Janeiro, Brazil, July 11-14, 2021.
  

• Globally Convergent Algorithms For Learning Multivariate Generalized Gaussian Distributions
  Bin Wang, Huanyu Zhang, Ziping Zhao, Ying Sun,
  IEEE Statistical Signal Processing Workshop (SSP), Rio de Janeiro, Brazil, July 11-14, 2021.
  

• A Deep Learning-Aided Approach to Portfolio Design for Financial Index Tracking
  Zepeng Zhang, Ziping Zhao,
  Annual Asilomar Conference on Signals, Systems, and Computers (Asilomar), Pacific Grove, CA, USA, Nov. 1-4, 2020.
  

• Online Robust Reduced-Rank Regression
  Yangzhuoran Fin Yang, Ziping Zhao,
  IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM), Hangzhou, China, June 8-11, 2020.
  Best Student Paper Award Finalist

• Joint Transmit Waveforms and Receive Filters Design for Large-Scale MIMO Beampattern Synthesis
  Ziping Zhao,
  IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM), Hangzhou, China, June 8-11, 2020.
  

• FUSIONNDVI: A Novel Fusion Method for NDVI in Remote Sensing
  Mengliang Zhang, Ziping Zhao, Yuerong Chen, Zhongyuan Wang, Xin Tian,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Barcelona, Spain, May 4-8, 2020.
  

• Large-Scale Regularized Portfolio Selection via Convex Optimization
  Ziping Zhao, Daniel P. Palomar,
  IEEE Global Conference on Signal and Information Processing (GlobalSIP), Ottawa, ON, Canada, Nov. 11-14, 2019.
  Invited Paper

• Perturbed Projected Gradient Descent Converges To Approximate Second-Order Points For Bound Constrained Nonconvex Problems
  Ziping Zhao*, Songtao Lu*, Kejun Huang, Mingyi Hong, (* = eq. contr.)
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Brighton, UK, May 12-17, 2019.
  

• Unified Framework For Minimax MIMO Transmit Beampattern Matching Under Waveform Constraints
  Ziping Zhao*, Rui Zhou*, Daniel P. Palomar, (* = eq. contr.)
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Brighton, UK, May 12-17, 2019.
  

• Distributed Optimization for Generalized Phase Retrieval over Networks
  Ziping Zhao, Songtao Lu, Mingyi Hong, Daniel P. Palomar,
  Annual Asilomar Conference on Signals, Systems, and Computers (Asilomar), Pacific Grove, CA, USA, Oct. 28-31, 2018.
  

• Limited Feedback Double Directional Massive MIMO Channel Estimation: From Low-Rank Modeling to Deep Learning
  Haoran Sun, Ziping Zhao, Xiao Fu, Mingyi Hong,
  IEEE International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), Kalamata, Greece, June 25-28, 2018.
  Invited Paper

• Optimal Portfolio Design for Statistical Arbitrage in Finance
  Ziping Zhao, Rui Zhou, Zhongju Wang, Daniel P. Palomar,
  IEEE Statistical Signal Processing Workshop (SSP), Freiburg, Germany, June 10-13, 2018.
  

• Sparse Reduced Rank Regression with Nonconvex Regularization
  Ziping Zhao, Daniel P. Palomar,
  IEEE Statistical Signal Processing Workshop (SSP), Freiburg, Germany, June 10-13, 2018.
  

• MIMO Transmit Beampattern Matching under Waveform Constraints
  Ziping Zhao, Daniel P. Palomar,
  IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP), Calgary, AB, Canada, April 15-20, 2018.
  

• Robust Maximum Likelihood Estimation of Sparse Vector Error Correction Model
  Ziping Zhao, Daniel P. Palomar,
  IEEE Global Conference on Signal and Information Processing (GlobalSIP), Montreal, QC, Canada, Nov. 14-16, 2017.
  

• Mean-Reverting Portfolio Design via Majorization-Minimization Method
  Ziping Zhao, Daniel P. Palomar,
  Annual Asilomar Conference on Signals, Systems, and Computers (Asilomar), Pacific Grove, CA, USA, Nov. 6-9, 2016.
  

Ph.D. Thesis

• Ziping Zhao, “Signal Processing and Machine Learning for Statistical Arbitrage in Finance: Models, Algorithms, and Analysis,” Ph.D. dissertation, the Hong Kong University of Science and Technology, Hong Kong, Aug. 2019