collaborators

14 papers

cs.CL2026

LLMs Know the Constraint But Do Not Use It: Activation Bottlenecks in Pragmatic Constraint Reasoning

Yubo Li, Ramayya Krishnan, Rema Padman

When a salient surface cue competes with an implicit feasibility constraint, LLMs often fail -- but aggregate accuracy conflates genuine constraint inference with conservative defa…

cs.CY2026

Auditing Institutional Heterogeneity for Generative AI in Patient Education: A Large-Scale Study of 102 US Transplant Handbooks

Yubo Li, Rema Padman, Ramayya Krishnan

Health systems are rapidly deploying generative AI assistants that answer patient questions from institution-authored education materials, on the premise that grounding in local co…

cs.CL2026

The Model Says Walk: How Surface Heuristics Override Implicit Constraints in LLM Reasoning

Yubo Li, Lu Zhang, Tianchong Jiang +2

Large language models fail when a salient surface cue conflicts with an unstated feasibility constraint. We introduce the Heuristic Override Benchmark (HOB): 500 instances spanning…

cs.AI2026

The Chain Holds, the Answer Folds: Trace-Answer Dissociation in Reasoning Models Under Adversarial Pressure

Yubo Li, Ramayya Krishnan, Rema Padman

Reasoning models are evaluated on single-turn benchmarks but deployed in multi-turn dialogue, where users push back on correct answers. Under sustained adversarial pressure we find…

cs.CL2026

Same Question, Different Source, Different Answer: Auditing Source-Dependence in Medical Multi-Source RAG

Yubo Li, Rema Padman, Ramayya Krishnan

A retrieval-augmented generation (RAG) system deployed over a multi-author institutional corpus can give a different answer to the same question depending on which source it retrie…

cs.CL2026

Beyond Single-Turn: A Survey on Multi-Turn Interactions with Large Language Models

Yubo Li, Xiaobin Shen, Yidi Miao +4

Recent advances in large language models (LLMs) have substantially improved single-turn task performance, yet real-world applications increasingly demand sophisticated multi-turn i…