collaborators

11 papers

cs.AI2026

More Debate, Same Evidence: Structural Limits of Homogeneous Multi-Agent Groundedness

Yuelyu Ji

Large language model (LLM) judges are increasingly organized as multi-agent panels under the assumption that exchanging critiques improves judgment quality. We test this assumption…

cs.CL2026

What Makes a Medical Checker Trainable? Diagnosing Signal Collapse and Reward Hacking in Checker-Guided RAG for Biomedical QA

Yuelyu Ji, Min Gu Kwak, Hang Zhang +3

Medical RAG needs evidence-grounded claims, so plugging a claim-level NLI checker into retrieval-augmented RL is intuitive. \textbf{We find that the checker's \emph{output distribu…

cs.CL2026

StepGap: A Hybrid NLI-LLM Checker for Step-Level Evidence-Gap Detectionin Multi-Hop Question Answering

Yuelyu Ji, Zhuochun Li, Hui Ji +1

We present \textbf{StepGap}, a hybrid NLI-LLM decision tree that detects step-level evidence gaps in multi-hop QA and emits one of three typed labels: \textsc{Contradicted Claim} (…

cs.CY2026

A Scoping Review of LLM-as-a-Judge in Healthcare and the MedJUDGE Framework

Chenyu Li, Zohaib Akhtar, Mingu Kwak +13

As large language models (LLMs) increasingly generate and process clinical text, scalable evaluation has become critical. LLM-as-a-Judge (LaaJ), which uses LLMs to evaluate model o…

cs.AI2026

Scaling Medical Reasoning Verification via Tool-Integrated Reinforcement Learning

Hang Zhang, Ruheng Wang, Yuelyu Ji +7

Large language models have achieved strong performance on medical reasoning benchmarks, yet their deployment in clinical settings demands rigorous verification to ensure factual ac…

cs.CL2026

MRAG-Suite: A Diagnostic Evaluation Platform for Visual Retrieval-Augmented Generation

Yuelyu Ji, Wuwei Lan, Patrick NG

Multimodal Retrieval-Augmented Generation (Visual RAG) significantly advances question answering by integrating visual and textual evidence. Yet, current evaluations fail to system…