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Zheng Xu

32 accepted papers

2026

ACTG-ARL: Differentially Private Conditional Text Generation with RL-Boosted Control

ICML 2026poster

Generating high-quality synthetic text under differential privacy (DP) is critical for training and evaluating language models without compromising user privacy. Prior work on synthesizing DP *datasets* often fail to preserve key statistical attributes, suffer utility loss from the noise required by…

Cited by 0SourcecodeScholar
2026

Closed-Loop Cross-Scale Motion of Decoupled Light and Tendon Driven Miniature Continuum Robots

ICRA 2026poster

Small-scale robots are rapidly advancing in diverse fields such as industry and medicine. To be effective, they must be capable of accessing narrow, tortuous, or otherwise hard-to-reach environments and performing precise manipulation. This paper presents a vision-based closed-loop motion control sc…

Cited by 0Scholar
2026

Multifunctional Proximity-Aware Skin With Multizone ToF Sensing for AR-Assisted Human-Robot Interactive Telesurgery

RA-L 2026

Augmented Reality (AR)-assisted telesurgery has proven its effectiveness in enhancing situational awareness for clinician-side teleoperators. However, for patient-side surgical assistants, existing systems lack intuitive and safe interaction strategies to mitigate preoperative infection risks and in

Cited by 0SourceScholar
2025

Debiasing Federated Learning with Correlated Client Participation

ICLR 2025poster

In cross-device federated learning (FL) with millions of mobile clients, only a small subset of clients participate in training in every communication round, and Federated Averaging (FedAvg) is the most popular algorithm in practice. Existing analyses of FedAvg usually assume the participating clie…

Cited by 0SourcePDFScholar
2025

Last-Iterate Convergence of Smooth Regret Matching$^+$ Variants in Learning Nash Equilibria

NeurIPS 2025poster

Regret Matching$^+$ (RM$^+$) variants are widely used to build superhuman Poker AIs, yet few studies investigate their last-iterate convergence in learning a Nash equilibrium (NE). Although their last-iterate convergence is established for games satisfying the Minty Variational Inequality (MVI), no…

Cited by 0SourcecodeScholar
2025

Synthesizing Privacy-Preserving Text Data via Finetuning *without* Finetuning Billion-Scale LLMs

ICML 2025poster

Synthetic data offers a promising path to train models while preserving data privacy. Differentially private (DP) finetuning of large language models (LLMs) as data generator is effective, but is impractical when computation resources are limited. Meanwhile, prompt-based methods such as private evol…

Cited by 0SourcePDFScholar
2024

A Hassle-free Algorithm for Strong Differential Privacy in Federated Learning Systems

EMNLP 2024industry

Differential privacy (DP) and federated learning (FL) are combined as advanced privacy-preserving methods when training on-device language models in production mobile keyboard applications. DP-Follow-the-Regularized-Leader (DP-FTRL) algorithms, leveraging correlated noise mechanisms such as tree agg…

Cited by 1SourcePDFScholar
2024

Can Public Large Language Models Help Private Cross-device Federated Learning?

NAACL 2024findings

We study (differentially) private federated learning (FL) of language models. The language models in cross-device FL are relatively small, which can be trained with meaningful formal user-level differential privacy (DP) guarantees when massive parallelism in training is enabled by the participation…

Cited by 45SourcePDFScholar
2024

Heterogeneous LoRA for Federated Fine-tuning of On-Device Foundation Models

EMNLP 2024main

Foundation models (FMs) adapt surprisingly well to downstream tasks with fine-tuning. However, their colossal parameter space prohibits their training on resource-constrained edge-devices. For federated fine-tuning, we need to consider the smaller FMs of few billion parameters at most, namely on-dev…

Cited by 57SourcePDFScholar
2024

Improved Communication-Privacy Trade-offs in $L_2$ Mean Estimation under Streaming Differential Privacy

ICML 2024poster

We study $L_2$ mean estimation under central differential privacy and communication constraints, and address two key challenges: firstly, existing mean estimation schemes that simultaneously handle both constraints are usually optimized for $L_\infty$ geometry and rely on random rotation or Kashin's…

Cited by 3SourcePDFScholar
2024

Privacy-Preserving Instructions for Aligning Large Language Models

ICML 2024poster

Service providers of large language model (LLM) applications collect user instructions in the wild and use them in further aligning LLMs with users' intentions. These instructions, which potentially contain sensitive information, are annotated by human workers in the process. This poses a new privac…

2024

Safe and Robust Subgame Exploitation in Imperfect Information Games

ICML 2024poster

Opponent exploitation is an important task for players to exploit the weaknesses of others in games. Existing approaches mainly focus on balancing between exploitation and exploitability but are often vulnerable to modeling errors and deceptive adversaries. To address this problem, our paper offers…

Cited by 2SourcePDFScholar
2024

User Inference Attacks on Large Language Models

EMNLP 2024main

Text written by humans makes up the vast majority of the data used to pre-train and fine-tune large language models (LLMs). Many sources of this data—like code, forum posts, personal websites, and books—are easily attributed to one or a few “users”. In this paper, we ask if it is possible to infer i…

Cited by 28SourcePDFScholar
2023

(Amplified) Banded Matrix Factorization: A unified approach to private training

NeurIPS 2023poster

Matrix factorization (MF) mechanisms for differential privacy (DP) have substantially improved the state-of-the-art in privacy-utility-computation tradeoffs for ML applications in a variety of scenarios, but in both the centralized and federated settings there remain instances where either MF cannot…

Cited by 35SourcePDFScholar
2023

Beyond Uniform Lipschitz Condition in Differentially Private Optimization

ICML 2023poster

Most prior results on differentially private stochastic gradient descent (DP-SGD) are derived under the simplistic assumption of uniform Lipschitzness, i.e., the per-sample gradients are uniformly bounded. We generalize uniform Lipschitzness by assuming that the per-sample gradients have sample-depe…

Cited by 25SourcePDFScholar
2023

Federated Learning of Gboard Language Models with Differential Privacy

ACL 2023industry

We train and deploy language models (LMs) with federated learning (FL) and differential privacy (DP) in Google Keyboard (Gboard). The recent DP-Follow the Regularized Leader (DP-FTRL) algorithm is applied to achieve meaningfully formal DP guarantees without requiring uniform sampling of clients. To…

2023

Learning To Generate Image Embeddings With User-Level Differential Privacy

CVPR 2023poster

Small on-device models have been successfully trained with user-level differential privacy (DP) for next word prediction and image classification tasks in the past. However, existing methods can fail when directly applied to learn embedding models using supervised training data with a large class sp…

2023

On the Convergence of Federated Averaging with Cyclic Client Participation

ICML 2023poster

Federated Averaging (FedAvg) and its variants are the most popular optimization algorithms in federated learning (FL). Previous convergence analyses of FedAvg either assume full client participation or partial client participation where the clients can be uniformly sampled. However, in practical cro…

Cited by 37SourcePDFScholar
2022

Diurnal or Nocturnal? Federated Learning of Multi-branch Networks from Periodically Shifting Distributions

ICLR 2022poster

Federated learning has been deployed to train machine learning models from decentralized client data on mobile devices in practice. The clients available for training are observed to have periodically shifting distributions changing with the time of day, which can cause instability in training and d…

Cited by 35SourcePDFScholar
2021

GradInit: Learning to Initialize Neural Networks for Stable and Efficient Training

NeurIPS 2021poster

Innovations in neural architectures have fostered significant breakthroughs in language modeling and computer vision. Unfortunately, novel architectures often result in challenging hyper-parameter choices and training instability if the network parameters are not properly initialized. A number of ar…

2021

Practical and Private (Deep) Learning Without Sampling or Shuffling

ICML 2021spotlight

We consider training models with differential privacy (DP) using mini-batch gradients. The existing state-of-the-art, Differentially Private Stochastic Gradient Descent (DP-SGD), requires \emph{privacy amplification by sampling or shuffling} to obtain the best privacy/accuracy/computation trade-offs…

Cited by 226SourcePDFScholar
2020

The Impact of Neural Network Overparameterization on Gradient Confusion and Stochastic Gradient Descent

ICML 2020poster

This paper studies how neural network architecture affects the speed of training. We introduce a simple concept called gradient confusion to help formally analyze this. When gradient confusion is high, stochastic gradients produced by different data samples may be negatively correlated, slowing down…

Cited by 121SourcePDFScholar
2019

Adversarial training for free!

NeurIPS 2019poster

Adversarial training, in which a network is trained on adversarial examples, is one of the few defenses against adversarial attacks that withstands strong attacks. Unfortunately, the high cost of generating strong adversarial examples makes standard adversarial training impractical on large-scale pr…

Cited by 1720SourcePDFScholar
2018

Stabilizing Adversarial Nets with Prediction Methods

ICLR 2018poster

Adversarial neural networks solve many important problems in data science, but are notoriously difficult to train. These difficulties come from the fact that optimal weights for adversarial nets correspond to saddle points, and not minimizers, of the loss function. The alternating stochastic gradien…

2018

Visualizing the Loss Landscape of Neural Nets

NeurIPS 2018poster

Neural network training relies on our ability to find "good" minimizers of highly non-convex loss functions. It is well known that certain network architecture designs (e.g., skip connections) produce loss functions that train easier, and well-chosen training parameters (batch size, learning rate, o…

2017

Adaptive Consensus ADMM for Distributed Optimization

ICML 2017poster

The alternating direction method of multipliers (ADMM) is commonly used for distributed model fitting problems, but its performance and reliability depend strongly on user-defined penalty parameters. We study distributed ADMM methods that boost performance by using different fine-tuned algorithm par…

Cited by 89SourcePDFScholar
2017

Adaptive Relaxed ADMM: Convergence Theory and Practical Implementation

CVPR 2017poster

Many modern computer vision and machine learning applications rely on solving difficult optimization problems that involve non-differentiable objective functions and constraints. The alternating direction method of multipliers (ADMM) is a widely used approach to solve such problems. Relaxed ADMM is…

Cited by 57PDFScholar
2017

Training Quantized Nets: A Deeper Understanding

NeurIPS 2017poster

Currently, deep neural networks are deployed on low-power portable devices by first training a full-precision model using powerful hardware, and then deriving a corresponding low-precision model for efficient inference on such systems. However, training models directly with coarsely quantized weight…

Cited by 257SourcePDFScholar
2016

Training Neural Networks Without Gradients: A Scalable ADMM Approach

ICML 2016poster

With the growing importance of large network models and enormous training datasets, GPUs have become increasingly necessary to train neural networks. This is largely because conventional optimization algorithms rely on stochastic gradient methods that don’t scale well to large numbers of cores in a…

Cited by 341SourcePDFScholar