collaborators

7 papers

cs.LG2026

RUBRIC-ARROW: Alternating Pointwise Rubric Reward Modeling for LLM Post-training in Non-verifiable Domains

Haoxiang Jiang, Zihan Dong, Tianci Liu +5

Pointwise reward modeling offers critical signals for LLM post-training, yet struggles with absolute scoring in subjective, non-verifiable settings. Rubric-based methods address th…

cs.CL2026

Alternating Reinforcement Learning for Rubric-Based Reward Modeling in Non-Verifiable LLM Post-Training

Ran Xu, Tianci Liu, Zihan Dong +6

Standard reward models typically predict scalar scores that fail to capture the multifaceted nature of response quality in non-verifiable domains, such as creative writing or open-…

cs.AI2025

Knowledge Graph Augmented Large Language Models for Disease Prediction

Ruiyu Wang, Tuan Vinh, Ran Xu +5

Electronic health records (EHRs) enable strong clinical prediction, but explanations are often coarse and hard to use for patient-level decisions. We propose a knowledge graph (KG)…

cs.CL2025

Incentivizing Agentic Reasoning in LLM Judges via Tool-Integrated Reinforcement Learning

Ran Xu, Jingjing Chen, Jiayu Ye +4

Large Language Models (LLMs) are widely used as judges to evaluate response quality, providing a scalable alternative to human evaluation. However, most LLM judges operate solely o…

cs.CL2025

OpenRubrics: Towards Scalable Synthetic Rubric Generation for Reward Modeling and LLM Alignment

Tianci Liu, Ran Xu, Tony Yu +4

Reward modeling lies at the core of reinforcement learning from human feedback (RLHF), yet most existing reward models rely on scalar or pairwise judgments that fail to capture the…

cs.AI2025

HypKG: Hypergraph-based Knowledge Graph Contextualization for Precision Healthcare

Yuzhang Xie, Xu Han, Ran Xu +3

Knowledge graphs (KGs) are important products of the semantic web, which are widely used in various application domains. Healthcare is one of such domains where KGs are intensively…

cs.CL2025

RAG in the Wild: On the (In)effectiveness of LLMs with Mixture-of-Knowledge Retrieval Augmentation

Ran Xu, Yuchen Zhuang, Yue Yu +3

Retrieval-augmented generation (RAG) enhances large language models (LLMs) by integrating external knowledge retrieved at inference time. While RAG demonstrates strong performance…