activity
20242026
most citedA Statistical Framework of Watermarks for Large Language Models: Pivot, Detection Efficiency and Optimal Rules

17 citations · 26 across the 16 of their papers we have counts for

collaborators

18 papers

cs.CL2026

Conformal Prediction with Paraphrase-Aware Scoring for LLM Uncertainty Quantification

Jiayi Xin, Evan Qiang, Zihan Zhu +3

Uncertainty quantification (UQ) for large language models (LLMs) aims to provide reliable measures of predictive confidence, yet current methods are often unstable under meaning-pr…

stat.ME2026

Optimal Watermark Localization in Mixed-Source Large Language Model Texts

Jose H. Blanchet, T. Tony Cai, Xiang Li +3

Watermarking provides a principled way to authenticate text generated by large language models (LLMs). In practice, however, the final text may be mixed-source, with watermark evid…

cs.LG2026

CurveRL: Principled Distribution-Aware Context Reweighting for LLM Reasoning

Ke Sun, Yizhou Zhao, Jiayi Xin +2

Context or prompt-level reweighting has emerged as a central algorithmic lever in Reinforcement Learning with Verified Rewards (RLVR) for improving the reasoning capability of larg…

cs.LG2026

Improving the Trade-off Between Watermark Strength and Speculative Sampling Efficiency for Language Models

Weiqing He, Xiang Li, Li Shen +2

Watermarking is a principled approach for tracing the provenance of large language model (LLM) outputs, but its deployment in practice is hindered by inference inefficiency. Specul…

cs.CR2025

Robust Spectral Watermark for Synthetic Tabular Data

Yizhou Zhao, Xiang Li, Peter Song +2

The rise of generative AI has enabled the production of high-fidelity synthetic tabular data across fields such as healthcare, finance, and public policy, raising growing concerns…

math.ST2025

Optimal Detection for Language Watermarks with Pseudorandom Collision

T. Tony Cai, Xiang Li, Qi Long +2

Text watermarking plays a crucial role in ensuring the traceability and accountability of large language model (LLM) outputs and mitigating misuse. While promising, most existing m…

cs.LG2025

On the Empirical Power of Goodness-of-Fit Tests in Watermark Detection

Weiqing He, Xiang Li, Tianqi Shang +3

Large language models (LLMs) raise concerns about content authenticity and integrity because they can generate human-like text at scale. Text watermarks, which embed detectable sta…

stat.ML2025

Theoretical Tensions in RLHF: Reconciling Empirical Success with Inconsistencies in Social Choice Theory

Jiancong Xiao, Zhekun Shi, Kaizhao Liu +2

Despite its empirical success, Reinforcement Learning from Human Feedback (RLHF) has been shown to violate almost all the fundamental axioms in social choice theory -- such as majo…

stat.ML2025

Optimal Estimation of Watermark Proportions in Hybrid AI-Human Texts

Xiang Li, Garrett Wen, Weiqing He +3

Text watermarks in large language models (LLMs) are an increasingly important tool for detecting synthetic text and distinguishing human-written content from LLM-generated text. Wh…

cs.CL2025★ 1 cited

Evaluating the Unseen Capabilities: How Many Theorems Do LLMs Know?

Xiang Li, Jiayi Xin, Qi Long +1

Accurate evaluation of large language models (LLMs) is crucial for understanding their capabilities and guiding their development. However, current evaluations often inconsistently…

cs.GT2025

Fundamental Limits of Game-Theoretic LLM Alignment: Smith Consistency and Preference Matching

Zhekun Shi, Kaizhao Liu, Qi Long +2

Nash Learning from Human Feedback is a game-theoretic framework for aligning large language models (LLMs) with human preferences by modeling learning as a two-player zero-sum game.…

math.OC2025

Riemannian EXTRA: Communication-efficient decentralized optimization over compact submanifolds with data heterogeneity

Jiayuan Wu, Zhanwang Deng, Jiang Hu +2

We consider decentralized optimization over a compact Riemannian submanifold in a network of agents, where each agent holds a smooth, nonconvex local objective defined by its p…

math.OC2025

PolarGrad: A Class of Matrix-Gradient Optimizers from a Unifying Preconditioning Perspective

Tim Tsz-Kit Lau, Qi Long, Weijie Su

The ever-growing scale of deep learning models and training data underscores the critical importance of efficient optimization methods. While preconditioned gradient methods such a…

cs.GT2025

Statistical Impossibility and Possibility of Aligning LLMs with Human Preferences: From Condorcet Paradox to Nash Equilibrium

Kaizhao Liu, Qi Long, Zhekun Shi +2

Aligning large language models (LLMs) with diverse human preferences is critical for ensuring fairness and informed outcomes when deploying these models for decision-making. In thi…

stat.ME2024★ 1 cited

Robust Detection of Watermarks for Large Language Models Under Human Edits

Xiang Li, Feng Ruan, Huiyuan Wang +2

Watermarking has offered an effective approach to distinguishing text generated by large language models (LLMs) from human-written text. However, the pervasive presence of human ed…

stat.ML2024★ 1 cited

Debiasing Watermarks for Large Language Models via Maximal Coupling

Yangxinyu Xie, Xiang Li, Tanwi Mallick +2

Watermarking language models is essential for distinguishing between human and machine-generated text and thus maintaining the integrity and trustworthiness of digital communicatio…

stat.ML2024★ 6 cited

On the Algorithmic Bias of Aligning Large Language Models with RLHF: Preference Collapse and Matching Regularization

Jiancong Xiao, Ziniu Li, Xingyu Xie +4

Accurately aligning large language models (LLMs) with human preferences is crucial for informing fair, economically sound, and statistically efficient decision-making processes. Ho…

math.ST2024★ 17 cited

A Statistical Framework of Watermarks for Large Language Models: Pivot, Detection Efficiency and Optimal Rules

Xiang Li, Feng Ruan, Huiyuan Wang +2

Since ChatGPT was introduced in November 2022, embedding (nearly) unnoticeable statistical signals into text generated by large language models (LLMs), also known as watermarking,…