Research

Learning systems,
under the surface.

I study the representations and mechanisms that shape model behavior—then use statistical tools to make those behaviors more reliable, interpretable, and causally meaningful.

01 / Agenda

Research agenda.

Three connected directions guide my current questions.

Pillar 01

Diffusion Language Models & Representation Learning

I am interested in how diffusion-based language models organize and transform information, and how their internal representations differ from autoregressive systems.

DLLMsRepresentations
Pillar 02

Causal Machine Learning & Pre-trained PFNs

I explore causal effect estimation and causal reasoning, including how pre-trained prior-data fitted networks can support fast, principled inference.

Causal effectsPFNs
Pillar 03

Mechanistic Interpretability & Conformal Inference

I use interpretability and uncertainty quantification to ask what language models compute, when their outputs can be trusted, and how reliability can be measured.

InterpretabilityUncertainty
02 / Publications

Published work.

Peer-reviewed contributions in machine learning and clinical research.

Diagram for the FANS causal mechanism shift framework

ICML 2026 · Proceedings

Dissecting Causal Mechanism Shifts via FANS: Function and Noise Separation

Gyeongdeok Seo, Jaeyoon Shim, Mingyu Kim, Hoyoon Byun, Yonghan Jung, Kyungwoo Song

FANS offers a unified framework for causal mechanism shifts by separating changes in causal functions from changes in noise. Independence checks between estimated noise and parent variables distinguish function-driven and noise-driven shifts while accommodating complex noise changes.

Proceedings of the 43rd International Conference on Machine Learning, 2026

IJID 2026 · Original research

Static and Dynamic Scoring Systems for Post-acute Sequelae of SARS-CoV-2 in a Korean Cohort

Gyeongdeok Seo*, Hyejin Joo*, Kyungwoo Song, Mingyu Kim, Eunju Jang, Eusuk Kim, Jaehoon Ko, Jinseo Lee, Joonyoung Song, Junwon Seo, Junyong Choi, Kitae Kwon, Seungsoon Lee, Wanbeom Park, Wonsuk Choi, Yaejee Baek, Yongkyun Kim, Hyewon Jeong, Jaehun Jung, Jacob Lee

This collaborative study develops static and dynamic scoring systems for post-acute sequelae of SARS-CoV-2 using evidence from a Korean cohort.

* Equal contribution.

International Journal of Infectious Diseases, 2026
03 / Experience

Research in context.

Methodological work grounded in real questions and cross-disciplinary collaboration.

Aug. 2025 — Feb. 2026

Statistical Consultation Researcher

Institute of Data Science
Department of Statistics and Data Science, Yonsei University

Provided statistical consultation across disciplines, including research in New Testament studies and environmental finance.

ConsultingApplied statistics

Jul. 2024 — Feb. 2025

Undergraduate Research Assistant

Machine Learning and Artificial Intelligence Lab
Yonsei University · Advisor: Prof. Kyungwoo Song

Reviewed research on LLM reasoning, causal inference, and sharpness-aware minimization, building the foundation for my current research directions.

LLM reasoningCausal inference