collaborators

8 papers

cs.LG2026

Beyond Post-Hoc Temperature Scaling: Bilevel Optimization for LLM Calibration

Ruochen Jin, Zhanliang Wang, Zongyu Dai +2

Preference alignment often makes large language models (LLMs) overconfident and poorly calibrated. Traditional post-hoc temperature scaling is inherently domain-dependent: a temper…

cs.CL2026

A Semantic-Sampling Framework for Evaluating Calibration in Open-Ended Question Answering

Zhanliang Wang, Jiancong Xiao, Ruochen Jin +3

Calibration measures whether a model's predicted confidence aligns with its empirical accuracy, and is central to the reliable deployment of large language models (LLMs) in high-st…

cs.GT2026

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…

cs.LG2025

Restoring Calibration for Aligned Large Language Models: A Calibration-Aware Fine-Tuning Approach

Jiancong Xiao, Bojian Hou, Zhanliang Wang +4

One of the key technologies for the success of Large Language Models (LLMs) is preference alignment. However, a notable side effect of preference alignment is poor calibration: whi…

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…

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.…