collaborators

10 papers

cs.CL2026

When Correct Decisions Hide Internal Stress: Decision-State Probing in Multimodal Language Models

Haoran Zhao, Soyeon Caren Han, Eduard Hovy

Multimodal language models are typically evaluated through external behavior: selecting the correct image--text match, rejecting unsupported captions, or answering visual queries c…

cs.CL2026

Inclusion-of-Thoughts: Mitigating Preference Instability via Purifying the Decision Space

Mohammad Reza Ghasemi Madani, Soyeon Caren Han, Shuo Yang +1

Multiple-choice questions (MCQs) are widely used to evaluate large language models (LLMs). However, LLMs remain vulnerable to the presence of plausible distractors. This often dive…

cs.AI2026

ToolTree: Efficient LLM Agent Tool Planning via Dual-Feedback Monte Carlo Tree Search and Bidirectional Pruning

Shuo Yang, Soyeon Caren Han, Yihao Ding +2

Large Language Model (LLM) agents are increasingly applied to complex, multi-step tasks that require interaction with diverse external tools across various domains. However, curren…

cs.CL2026

BRIDGE: Benchmark for multi-hop Reasoning In long multimodal Documents with Grounded Evidence

Biao Xiang, Soyeon Caren Han, Yihao Ding

Multi-hop question answering (QA) is widely used to evaluate the reasoning capabilities of large language models, yet most benchmarks focus on final answer correctness and overlook…

cs.AI2026

EvoTool: Self-Evolving Tool-Use Policy Optimization in LLM Agents via Blame-Aware Mutation and Diversity-Aware Selection

Shuo Yang, Soyeon Caren Han, Xueqi Ma +3

LLM-based agents depend on effective tool-use policies to solve complex tasks, yet optimizing these policies remains challenging due to delayed supervision and the difficulty of cr…

cs.CL2026

When More Is Less: A Systematic Analysis of Spatial and Commonsense Information for Visual Spatial Reasoning

Muku Akasaka, Soyeon Caren Han

Visual spatial reasoning (VSR) remains challenging for modern vision-language models (VLMs), despite advances in multimodal architectures. A common strategy is to inject additional…