Dongwoo Kim
Author directory2026
The Interplay of Harness Design and Post-training in LLM Agents
Kyungmin Kim | Youngbin Choi | Seoyeon Lee | Suhyeon Jun | Dongwoo Kim | Sangdon Park
Findings of the Association for Computational Linguistics: EMNLP 2026
Kyungmin Kim | Youngbin Choi | Seoyeon Lee | Suhyeon Jun | Dongwoo Kim | Sangdon Park
Findings of the Association for Computational Linguistics: EMNLP 2026
Tool-integrated LLM agents are often wrapped within a *harness*: the scaffolding that determines which tools are exposed, how they are described, and what auxiliary information accompanies each per-step observation. While agents are routinely post-trained, this scaffolding is typically treated as a *fixed* engineering detail, with design effort limited to the training-free regime. Moreover, existing post-training algorithms assume a static environment, even though tool environments and tasks often shift upon deployment. To address this gap, we extend ALFWorld (i) to treat the harness as a controllable design dimension and (ii) to support evaluation under task and tool environment shifts. Building on this, we systematically analyze how the harness design influences post-training in both in-distribution and out-of-distribution (OOD) settings. We empirically show that *harness-aware post-training* not only improves in-distribution performance but also enables agents to robustly adapt to OOD settings. Under a harness with minimal design effort, post-training suffers a drastic performance drop under stronger tool environment shifts, further highlighting the importance of harness-aware post-training under such shifts.
Plane Geometry Problem Solving with Multi-modal Reasoning: A Survey
Seunghyuk Cho | Zhenyue Qin | Yang Liu | Youngbin Choi | Seungbeom Lee | Dongwoo Kim
Findings of the Association for Computational Linguistics: EACL 2026
Seunghyuk Cho | Zhenyue Qin | Yang Liu | Youngbin Choi | Seungbeom Lee | Dongwoo Kim
Findings of the Association for Computational Linguistics: EACL 2026
Plane geometry problem solving (PGPS) has recently gained significant attention as a benchmark to assess the multi-modal reasoning capabilities of large vision-language models. Despite the growing interest in PGPS, the research community still lacks a comprehensive overview that systematically synthesizes recent work in PGPS. To fill this gap, we present a survey of existing PGPS studies. We first categorize PGPS methods into an encoder-decoder framework and summarize the corresponding output formats used by their encoders and decoders. Subsequently, we classify and analyze these encoders and decoders according to their architectural designs. Finally, we outline major challenges and promising directions for future research. In particular, we discuss the hallucination issues arising during the encoding phase within encoder-decoder architectures, as well as the problem of data leakage in current PGPS benchmarks.
Exploring Iterative Controllable Summarization with Large Language Models
Sangwon Ryu | Heejin Do | Daehui Kim | Hwanjo Yu | Dongwoo Kim | Yunsu Kim | Gary Lee | Jungseul Ok
Findings of the Association for Computational Linguistics: EACL 2026
Sangwon Ryu | Heejin Do | Daehui Kim | Hwanjo Yu | Dongwoo Kim | Yunsu Kim | Gary Lee | Jungseul Ok
Findings of the Association for Computational Linguistics: EACL 2026
Large language models (LLMs) have demonstrated remarkable performance in abstractive summarization tasks. However, their ability to precisely control summary attributes (e.g., length or topic) remains underexplored, limiting their adaptability to specific user preferences. In this paper, we systematically explore the controllability of LLMs. To this end, we revisit summary attribute measurements and introduce iterative evaluation metrics, failure rate and average iteration count, to more precisely evaluate controllability beyond assessment of errors. Our findings show that LLMs struggle more with numerical attributes than with linguistic attributes. To address this challenge, we propose a guide-to-explain framework (GTE) for controllable summarization. GTE enables the model to identify misaligned attributes in the initial draft and guides it to self-explain errors in the previous output. By encouraging reflection on attribute misalignment, GTE generates well-adjusted summaries that satisfy the desired attributes with robust effectiveness while requiring surprisingly fewer iterations than other iterative approaches.
Long Live the Librarian! A Persistent Search Sub-Agent for Energy-Efficient Multi-Agent Software Engineering Systems
Seunghyuk Cho | Sunghyun Choi | Jaeseung Heo | Youngbin Choi | Saemi Moon | MoonJeong Park | Dongwoo Kim
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Seunghyuk Cho | Sunghyun Choi | Jaeseung Heo | Youngbin Choi | Saemi Moon | MoonJeong Park | Dongwoo Kim
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Multi-agent systems (MAS) have substantially advanced autonomous software engineering (SWE), but their growing inference energy demands raise sustainability concerns. In this paper, we demonstrate that this cost is concentrated in an overlooked source: redundant output tokens generated across agents. Two empirical findings ground this claim. First, our per-token energy attribution for MAS reveals a sharp asymmetry: an output token consumes 30 to 1,000 times more energy than an input or cached token. Second, MAS inflate per-episode output because agents repeatedly re-explore overlapping repository regions. To address this inefficiency, we propose Librarian, a persistent search sub-agent that tracks repository-search history and suppresses redundant exploration actions across agents. By returning short references to file regions instead of full file excerpts, Librarian further reduces output-token volume. On SWE-Bench Verified and SWE-Bench-Live, Librarian reduces per-episode GPU energy consumption of existing multi-agent SWE systems by 11 to 30% while preserving task performance. Our code is available at https://github.com/ml-postech/Librarian.
In-Place Feedback: Reliable Refinement for Multi-Turn Expert-LLM Collaboration
Youngbin Choi | Minjong Lee | Saemi Moon | Seunghyuk Cho | Chaehyeon Chung | MoonJeong Park | Dongwoo Kim
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Youngbin Choi | Minjong Lee | Saemi Moon | Seunghyuk Cho | Chaehyeon Chung | MoonJeong Park | Dongwoo Kim
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
LLM-generated drafts often contain subtle factual or logical errors, yet prior work shows that models struggle to reliably integrate multi-turn feedback aimed at fixing them. We propose *in-place feedback*, an interaction paradigm in which the user directly edits the model’s previous response and the model continues generation from the edited context. In-place feedback consistently outperforms standard multi-turn feedback across five reasoning-intensive benchmarks while requiring fewer tokens, and our fine-grained analysis shows that it applies corrections more reliably and propagates them to subsequent reasoning. A user study with domain experts refining LLM-generated summaries corroborates these findings: participants report higher final-output satisfaction and substantially lower fatigue with in-place feedback, and a mixed strategy combining in-place and multi-turn feedback improves every dimension we measure. These results suggest that editing errors in place is a more reliable way to incorporate expert corrections than multi-turn feedback, while combining the two acts complementarily to form a more effective collaboration than either mechanism alone.
2025
GeoDANO: Geometric VLM with Domain Agnostic Vision Encoder
Seunghyuk Cho | Zhenyue Qin | Yang Liu | Youngbin Choi | Seungbeom Lee | Dongwoo Kim
Findings of the Association for Computational Linguistics: EMNLP 2025
Seunghyuk Cho | Zhenyue Qin | Yang Liu | Youngbin Choi | Seungbeom Lee | Dongwoo Kim
Findings of the Association for Computational Linguistics: EMNLP 2025
We introduce GeoDANO, a geometric vision-language model (VLM) with a domain-agnostic vision encoder, for solving plane geometry problems. Although VLMs have been employed for solving geometry problems, their ability to recognize geometric features remains insufficiently analyzed. To address this gap, we propose a benchmark that evaluates the recognition of visual geometric features, including primitives such as dots and lines, and relations such as orthogonality. Our preliminary study shows that vision encoders often used in general-purpose VLMs, e.g., OpenCLIP, fail to detect these features and struggle to generalize across domains. To overcome the limitation, we develop GeoCLIP, a CLIP-based model trained on synthetic geometric diagram–caption pairs. Benchmark results show that GeoCLIP outperforms existing vision encoders in recognizing geometric features. We then propose our VLM, GeoDANO, which augments GeoCLIP with a domain adaptation strategy for unseen diagram styles. GeoDANO outperforms specialized methods for plane geometry problems and GPT-4o on MathVerse. The implementation is available at https://github.com/ml-postech/GeoDANO.
ChronoBias: A Benchmark for Evaluating Time-conditional Group Bias in the Time-sensitive Knowledge of Large Language Models
Kyungmin Kim | Youngbin Choi | Hyounghun Kim | Dongwoo Kim | Sangdon Park
Findings of the Association for Computational Linguistics: EMNLP 2025
Kyungmin Kim | Youngbin Choi | Hyounghun Kim | Dongwoo Kim | Sangdon Park
Findings of the Association for Computational Linguistics: EMNLP 2025
In this paper, we propose ChronoBias, a novel benchmark for evaluating time-conditional group bias in the time-sensitive knowledge of large language models (LLMs).Our benchmark is constructed via a template-based semi-automated generation method, balancing the quality-quantity trade-off in existing benchmark curation approaches.For knowledge that changes over time, time-conditional group bias exhibits varying patterns across time intervals, evident in both the best- and worst-performing groups and in the bias metric itself.In addition to parametric knowledge bias–which influences group bias across all time intervals–we identify time-sensitivity bias as an additional factor after a model’s knowledge cutoff, accounting for much of the variation in time-conditional group bias over time.Since both biases are irreducible, retrieval-augmented generation (RAG) can be a promising approach, as it can address post-cutoff knowledge and better leverage pretraining knowledge that is underrepresented in the model parameters.While RAG improves both overall performance and group bias, we observe that the disparate patterns of time-conditional group bias still persist.Therefore, through extensive experiments with various model configurations, we illustrate how accurate and fair RAG-based LLMs should behave and provide actionable guidelines toward constructing such ideal models.
CoPL: Collaborative Preference Learning for Personalizing LLMs
Youngbin Choi | Seunghyuk Cho | Minjong Lee | MoonJeong Park | Yesong Ko | Jungseul Ok | Dongwoo Kim
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Youngbin Choi | Seunghyuk Cho | Minjong Lee | MoonJeong Park | Yesong Ko | Jungseul Ok | Dongwoo Kim
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Personalizing large language models (LLMs) is important for aligning outputs with diverse user preferences, yet existing methods struggle with flexibility and generalization. We propose CoPL (Collaborative Preference Learning), a graph-based collaborative filtering framework that models user-response relationships to enhance preference estimation, particularly in sparse annotation settings. By integrating a mixture of LoRA experts, CoPL efficiently fine-tunes LLMs while dynamically balancing shared and user-specific preferences. Additionally, an optimization-free adaptation strategy enables generalization to unseen users without fine-tuning. Experiments on TL;DR, UltraFeedback-P, and PersonalLLM datasets demonstrate that CoPL outperforms existing personalized reward models, effectively capturing both common and controversial preferences, making it a scalable solution for personalized LLM alignment.
Retrieval-Augmented Generation with Estimation of Source Reliability
Jeongyeon Hwang | Junyoung Park | Hyejin Park | Dongwoo Kim | Sangdon Park | Jungseul Ok
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Jeongyeon Hwang | Junyoung Park | Hyejin Park | Dongwoo Kim | Sangdon Park | Jungseul Ok
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Retrieval-Augmented Generation (RAG) is an effective approach to enhance the factual accuracy of large language models (LLMs) by retrieving information from external databases, which are typically composed of diverse sources, to supplement the limited internal knowledge of LLMs. However, the standard RAG often risks retrieving incorrect information, as it relies solely on relevance between a query and a document, overlooking the heterogeneous reliability of these sources. To address this issue, we propose Reliability-Aware RAG (RA-RAG), a new multi-source RAG framework that estimates the reliability of sources and leverages this information to prioritize highly reliable and relevant documents, ensuring more robust and accurate response generation. Specifically, RA-RAG first estimates source reliability by cross-checking information across multiple sources. It then retrieves documents from the top-𝜅 reliable and relevant sources and aggregates their information using weighted majority voting (WMV), where the selective retrieval ensures scalability while not compromising the performance. Comprehensive experiments show that RA-RAG consistently outperforms baselines in scenarios with heterogeneous source reliability while scaling efficiently as the number of sources increases. Furthermore, we demonstrate the ability of RA-RAG to estimate real-world sources’ reliability, highlighting its practical applicability. Our code and data are available at RA-RAG.
2020
word2word: A Collection of Bilingual Lexicons for 3,564 Language Pairs
Yo Joong Choe | Kyubyong Park | Dongwoo Kim
Proceedings of the Twelfth Language Resources and Evaluation Conference
Yo Joong Choe | Kyubyong Park | Dongwoo Kim
Proceedings of the Twelfth Language Resources and Evaluation Conference
We present word2word, a publicly available dataset and an open-source Python package for cross-lingual word translations extracted from sentence-level parallel corpora. Our dataset provides top-k word translations in 3,564 (directed) language pairs across 62 languages in OpenSubtitles2018 (Lison et al., 2018). To obtain this dataset, we use a count-based bilingual lexicon extraction model based on the observation that not only source and target words but also source words themselves can be highly correlated. We illustrate that the resulting bilingual lexicons have high coverage and attain competitive translation quality for several language pairs. We wrap our dataset and model in an easy-to-use Python library, which supports downloading and retrieving top-k word translations in any of the supported language pairs as well as computing top-k word translations for custom parallel corpora.
2017
Joint Modeling of Topics, Citations, and Topical Authority in Academic Corpora
Jooyeon Kim | Dongwoo Kim | Alice Oh
Transactions of the Association for Computational Linguistics, Volume 5
Jooyeon Kim | Dongwoo Kim | Alice Oh
Transactions of the Association for Computational Linguistics, Volume 5
Much of scientific progress stems from previously published findings, but searching through the vast sea of scientific publications is difficult. We often rely on metrics of scholarly authority to find the prominent authors but these authority indices do not differentiate authority based on research topics. We present Latent Topical-Authority Indexing (LTAI) for jointly modeling the topics, citations, and topical authority in a corpus of academic papers. Compared to previous models, LTAI differs in two main aspects. First, it explicitly models the generative process of the citations, rather than treating the citations as given. Second, it models each author’s influence on citations of a paper based on the topics of the cited papers, as well as the citing papers. We fit LTAI into four academic corpora: CORA, Arxiv Physics, PNAS, and Citeseer. We compare the performance of LTAI against various baselines, starting with the latent Dirichlet allocation, to the more advanced models including author-link topic model and dynamic author citation topic model. The results show that LTAI achieves improved accuracy over other similar models when predicting words, citations and authors of publications.
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Co-authors
- Youngbin Choi 7
- Seunghyuk Cho 5
- Jungseul Ok 3
- MoonJeong Park 3
- Sangdon Park 3
- Kyungmin Kim 2
- Minjong Lee 2
- Seungbeom Lee 2
- Yang Liu 2
- Saemi Moon 2
- Zhenyue Qin 2
- Yo Joong Choe 1
- Sunghyun Choi 1
- Chaehyeon Chung 1
- Heejin Do 1
- Jaeseung Heo 1
- Jeongyeon Hwang 1
- Suhyeon Jun 1
- Daehui Kim 1
- Hyounghun Kim 1
- Jooyeon Kim 1
- Yunsu Kim 1
- Yesong Ko 1
- Gary Geunbae Lee 1
- Seoyeon Lee 1
- Alice Oh 1
- Hyejin Park 1
- Junyoung Park 1
- Kyubyong Park 1
- Sangwon Ryu 1
- Hwanjo Yu 1