Ax Michal Valko, R\'emi Munos, Branislav Kveton, Tom\'a\v{s} Koc\'ak 4/21/2026

Spectral bandits for smooth graph functions

Bandit algorithm framework for online learning on graph-structured payoffs with applications to content recommendation systems.

Ax Jiaqi Wang (Beijing University of Posts and Telecommunications, Beijing Academy of Artificial Intelligence), Haoge Deng (Beijing Academy of Artificial Intelligence), Ting Pan (Beijing Academy of Artificial Intelligence), Yang Liu (Beijing Academy of Artificial Intelligence), Chengyuan Wang (Beijing Academy of Artificial Intelligence), Fan Zhang (Beijing Academy of Artificial Intelligence), Yonggang Qi (Beijing University of Posts and Telecommunications), Xinlong Wang (Beijing Academy of Artificial Intelligence) 4/21/2026

UDM-GRPO: Stable and Efficient Group Relative Policy Optimization for Uniform Discrete Diffusion Models

Framework for stable integration of reinforcement learning with uniform discrete diffusion models, addressing training instability in GRPO application.

Ax Joonhyuk Lee, Virginia Ma, Sarah Zhao, Yash Nair, Asher Spector, Regev Cohen, Emmanuel J. Cand\`es 4/21/2026

FUSE: Ensembling Verifiers with Zero Labeled Data

Unsupervised method for improving LLM verification by ensembling verifiers without labeled data, useful for training and deployment.

Ax Minji Lee, Colin Kalicki, Minkyu Jeon, Aymen Qabel, Alisia Fadini, Mohammed AlQuraishi 4/21/2026

ConforNets: Latents-Based Conformational Control in OpenFold3

Method for controlling protein conformational states in OpenFold3 via latent variable manipulation to capture biologically relevant alternate conformations.

Ax Yoonho Lee, Jonathan Williams, Henrik Marklund, Archit Sharma, Eric Mitchell, Anikait Singh, Chelsea Finn 4/21/2026

Test-Time Alignment via Hypothesis Reweighting

Method for real-time LLM personalization via hypothesis reweighting that adapts model outputs to individual user preferences with minimal labeled examples.

Ax Mingkuan Feng, Jinyang Wu, Siyuan Liu, Shuai Zhang, Hongjian Fang, Ruihan Jin, Feihu Che, Pengpeng Shao, Zhengqi Wen, Jianhua Tao 4/21/2026

Two-Stage Regularization-Based Structured Pruning for LLMs

Two-stage pruning method for reducing LLM parameters with regularization to preserve knowledge during deployment.

Ax An Vo, Khai-Nguyen Nguyen, Mohammad Reza Taesiri, Vy Tuong Dang, Anh Totti Nguyen, Daeyoung Kim 4/21/2026

Vision Language Models are Biased

Analysis of bias in vision-language models on objective visual tasks like counting and identification.

Ax Brendan Leigh Ross, No\"el Vouitsis, Atiyeh Ashari Ghomi, Rasa Hosseinzadeh, Ji Xin, Zhaoyan Liu, Yi Sui, Shiyi Hou, Kin Kwan Leung, Gabriel Loaiza-Ganem, Jesse C. Cresswell 4/21/2026

Textual Bayes: Quantifying Prompt Uncertainty in LLM-Based Systems

Method for quantifying uncertainty in LLM-based systems and prompt sensitivity without access to model internals.

Ax Luca Zhou, Pratham Yashwante, Marshall Fisher, Alessio Sampieri, Zihao Zhou, Fabio Galasso, Rose Yu 4/21/2026

CaTS-Bench: Can Language Models Describe Time Series?

CaTS-Bench benchmark for evaluating language models on time series captioning and temporal reasoning across 11 domains.

Ax Yoshihiko Ozaki, Shuhei Watanabe, Toshihiko Yanase 4/21/2026

OptunaHub: A Platform for Black-Box Optimization

OptunaHub platform for distributed black-box optimization components with unified interface, supporting AutoML and hyperparameter tuning.