collaborators

7 papers

cs.CY2025

Can You Share Your Story? Modeling Clients' Metacognition and Openness for LLM Therapist Evaluation

Minju Kim, Dongje Yoo, Yeonjun Hwang +11

Understanding clients' thoughts and beliefs is fundamental in counseling, yet current evaluations of LLM therapists often fail to assess this ability. Existing evaluation methods r…

cs.CL2025

One Missing Piece for Open-Source Reasoning Models: A Dataset to Mitigate Cold-Starting Short CoT LLMs in RL

Hyungjoo Chae, Dongjin Kang, Jihyuk Kim +6

With the release of R1, a publicly available large reasoning model (LRM), researchers commonly train new LRMs by training language models on R1's long chain-of-thought (CoT) infere…

cs.LG2025

Rethinking Reward Model Evaluation Through the Lens of Reward Overoptimization

Sunghwan Kim, Dongjin Kang, Taeyoon Kwon +3

Reward models (RMs) play a crucial role in reinforcement learning from human feedback (RLHF), aligning model behavior with human preferences. However, existing benchmarks for rewar…

cs.CL2025

ToolHaystack: Stress-Testing Tool-Augmented Language Models in Realistic Long-Term Interactions

Beong-woo Kwak, Minju Kim, Dongha Lim +5

Large language models (LLMs) have demonstrated strong capabilities in using external tools to address user inquiries. However, most existing evaluations assume tool use in short co…

cs.CL2025

Web-Shepherd: Advancing PRMs for Reinforcing Web Agents

Hyungjoo Chae, Sunghwan Kim, Junhee Cho +18

Web navigation is a unique domain that can automate many repetitive real-life tasks and is challenging as it requires long-horizon sequential decision making beyond typical multimo…

cs.CL2024

Coffee-Gym: An Environment for Evaluating and Improving Natural Language Feedback on Erroneous Code

Hyungjoo Chae, Taeyoon Kwon, Seungjun Moon +7

This paper presents Coffee-Gym, a comprehensive RL environment for training models that provide feedback on code editing. Coffee-Gym includes two major components: (1) Coffee, a da…