YOUNGMIN (YOUNG) KO
Evanston,USA
Overview
4
4
years of professional experience
Work History
World Model of Large Language Models
Northwestern & Yale Universities
01.2025 - 05.2025
- Co-authored LAMP: Extracting Locally Linear Decision Surfaces from LLM World Models (under review)
- Fits locally linear surrogates to LLM self-explanations, revealing how stated factors impact decisions, achieving R² values (e.g., 0.42±0.03 for GPT-4.1-mini) comparable to LIME with enhanced feature interpretability.
- Validated across sentiment, safety, and clinical tasks (e.g., gastroenterology expert agreement of 0.697 vs. 0.635 inter-expert baseline) showing LAMP outputs align with human judgment.
Diagnostic Reasoning With Large Language Models
Northwestern & Yale Universities
11.2024 - 03.2025
- Presented poster Automated Prompt Optimization Strategy Improves Large Language Model Diagnostic Accuracy for Complex Clinical Cases in Gastroenterology and Hepatology at Digestive Disease Week 2025
- Engineered an evolutionary prompt-optimization framework, boosting GPT-4.1-nano top-1 diagnostic accuracy on 262 real-world gastroenterology cases from 59.3% to 74.6% (15.3 pp increase).
AI Safety in Evidence-Based Medicine
Northwestern & Yale Universities
05.2023 - 09.2024
- Co-authored Expert-of-Experts Verification and Alignment (EVA) Framework for LLM Safety in Gastroenterology – accepted in npj Digital Medicine (Nature Portfolio journal)
- Benchmarked 9 open-source & proprietary LLMs (GPT-3.5/4/4o/1, Claude-3-Opus, Mixtral 7B, Llama-2 7B/13B/70B) across 27 baseline, RAG, and LoRA-SFT configurations, identifying a GPT-4o + RAG setup that exceeded board-certified accuracy by 12 pp
- Trained a reward model (OPT-350M) on 7k expert-graded answers, raising automated grading precision from 80.2 % to 87.9 % and enhancing end-to-end answer accuracy by 8.4 % via rejection sampling
REU on Stochastic Processes and Financial Time Series
Yeshiva University
06.2021 - 08.2021
- Detected anomalies in equities via Persistence Landscape by embedding daily returns time series data with Takens Embedding Theorem with gudhi package
- Presented the work Capturing Patterns in Equity Price Change via TDA under the guidance of Professor Marian Gidea in Yeshiva University Mathematical Physics seminar: REU student presentations
Teaching Assistant
Northwestern University
09.2023 - 12.2023
- STAT436: Reinforcement Learning, STAT362: Advanced ML for Data Science, STAT320: Statistical Theory&Methods, STAT304: Data Structures and Algorithms for Data Science
Team Lead
Northwestern University, English Language Program
06.2023 - 08.2023
- Led 8 peer mentors as a team lead in supporting 67 international graduate students, organizing weekly check-ins, delegating tasks, and providing resources to enhance discussions and engagement
Workshop Teaching Assistant
Northwestern University, Institute for Policy Research
06.2024 - 08.2024
- Provided instructional and logistical support for two intensive summer research training institutes for researchers:
- NSF-Funded Summer Research Training Institute: Improving Evaluations of R&D in STEM Education (July 8-12, 2024): Prepared instructional materials, led lab sessions, and assisted in breakout groups focusing on evaluation methodologies in STEM education research.
- IES-Funded Workshop: Randomized Control Trials (2024 RCT Summer Institute) (July 15-25, 2024): Mentored participant groups through daily group projects and analysis labs covering experimental design, statistical modeling, power analysis, and validity considerations in RCTs.
Group Leader
Northwestern University,
09.2024 - 11.2024
- Curated events as a group leader for 10+ participants per event at Chicago’s iconic venues to immerse international students in local culture and boost English confidence
Education
PhD Candidate - Statistics
Northwestern University
Evanston, IL06.2027
Bachelor of Science - Mathematics
Haverford College
Haverford, PA05.2022
Skills
- Programming: Python, R
- Frameworks: PyTorch, Langchain, Pandas, NumPy
- Tools: Git
- Machine Learning: Reinforcement Learning, NLP, Large Language Models, Reward Modeling
Awards
Haverford KINSC/Velay Summer Scholar Fellowship May 2021, Haverford First Year Math Prize Exam, Single Winner March 2017
Leadership & Teaching Experience
- Teaching Assistant: STAT346 (Reinforcement Learning), STAT362 (Advanced ML for Data Science), STAT320 (Statistical Theory&Methods), STAT304 (Data Structures and Algorithms for Data Science)
- Workshop Assistant: Improving Evaluations of R&D in STEM Education (NSF-Funded Summer Research Training Institute), 2024 Randomized Control Trials Summer Institute (IES-Funded Workshop)
- Group Leader: English Development through Guided Experience (EDGE), Northwestern University
- Team Lead: English Language Program (ELP), Northwestern University
Timeline
World Model of Large Language Models
Northwestern & Yale Universities
01.2025 - 05.2025
Diagnostic Reasoning With Large Language Models
Northwestern & Yale Universities
11.2024 - 03.2025
Group Leader
Northwestern University,
09.2024 - 11.2024
Workshop Teaching Assistant
Northwestern University, Institute for Policy Research
06.2024 - 08.2024
Teaching Assistant
Northwestern University
09.2023 - 12.2023
Team Lead
Northwestern University, English Language Program
06.2023 - 08.2023
AI Safety in Evidence-Based Medicine
Northwestern & Yale Universities
05.2023 - 09.2024
REU on Stochastic Processes and Financial Time Series
Yeshiva University
06.2021 - 08.2021
Bachelor of Science - Mathematics
Haverford College
PhD Candidate - Statistics
Northwestern University
Similar Profiles
Simeon ColvilleSimeon Colville
Voluntary Relay Worker at Universities and Colleges Christian FellowshipVoluntary Relay Worker at Universities and Colleges Christian Fellowship
William GreenWilliam Green
Research Assistant at Consortium of UniversitiesResearch Assistant at Consortium of Universities
ABIGAIL ALLOYEABIGAIL ALLOYE
Office Manager & Executive Assistant to the Secretary-General at African Research Universities Alliance (ARUA)Office Manager & Executive Assistant to the Secretary-General at African Research Universities Alliance (ARUA)
TRAVIS RENÈE HALLTRAVIS RENÈE HALL
Family Caregiver at Private CareFamily Caregiver at Private Care
Kohl ForrestKohl Forrest
Sr. Account Executive at AIT Truckload SolutionsSr. Account Executive at AIT Truckload Solutions