Stat&ML theory & methods on
Decision science - focusing on causal inference, multi-armed bandits, dynamic pricing
Multivariate data analysis - covariance matrices, precision matrices, clustering
Application & collaborations on
e-Commerce - 사용자 상호작용 기반의 컨텐츠 추천 최적화, 동적 가격결정, 실시간 입찰
Healthcare - 보건의료 빅데이터를 이용한 질병요인 탐색과 임상적 의사결정 보조
Manufacturing - 센서 데이터 기반 예지정비와 원인분석
[30] Youjia Zhang, Youngeun Kim, Young-Geun Choi, Hongyeob Kim, Huiling Liu, and Sungeun Hong* (2025). Backpropagation-Free Test-Time Adaptation via Probabilistic Gaussian Alignment. NeurIPS 2025. Link (available soon)
[29] Dongguen Kim, Young-Geun Choi, and Minwoo Chae* (2025). A Bayesian Approach to Contextual Dynamic Pricing using the Proportional Hazards Model with Discrete Price Data. NeurIPS 2025. Link (available soon)
[23] Young-Geun Choi, Gi-Soo Kim*, Seunghoon Paik and Myunghee Cho Paik* (2023). Semi-Parametric Contextual Bandits with Graph-Laplacian Regularization. Information Sciences 645:119367. Link
[21] Young-Geun Choi†, Soohyun Ahn† and Jayoun Kim* (2023). Model-based clustering for mixed data with sparse dependency structure. IEEE Access 11:75945-75954. Link
[20] Young-Geun Choi, Gi-Soo Kim, Yunseo Choi#, Woo Sung Cho, Myunghee Cho Paik, and Min-Hwan Oh* (2023). Semi-parametric contextual pricing algorithm using Cox proportional hazards model. The Proceedings of the 40th International Conference on Machine Learning (ICML), PMLR 202:5771-5786, 2023. Link
[18] Muxuan Liang, Young-Geun Choi, Yang Ning, Marueen Smith, and Ying-Qi Zhao* (2022). Estimation and inference on high-dimensional individualized treatment rule in observational data using split-and-pooled de-correlated score. Journal of Machine Learning Research 23(262):1-6. Link
[13] Young-Geun Choi, Seunghwan Lee, and Donghyeon Yu* (2022). An efficient parallel block coordinate descent algorithm for large-scale precision matrix estimation using graphics processing units. Computational Statistics, 37(1):419-443. Link
[12] Young-Geun Choi, Larry Hanrahan, Derek Norton, and & Ying-Qi Zhao* (2022). Simultaneous disease mapping and hot spot detection with application to childhood obesity surveillance from electronic health records. Biometrics 78(1):324-336. Link
[9] Seonghun Cho†, Young-Geun Choi†, Johan Lim, Won Jun Lee, Hyun-Jeong Bai, and Sungwon Kwon (2021). Test for uniformity of exchangeable random variables on the circle. Journal of the Korean Statistical Society 50:615–630. Link
[8] Seonghun Cho, Young-Geun Choi, Shota Katayama, and Johan Lim* (2021). Fixed support positive definite modification of covariance matrix by minimizing matrix L-infinity norm with applications to portfolio optimization. AStA Advances in Statistical Analysis 105:601–627. Link
[7] Young-Geun Choi, Anindya Roy, Junyong Park, and Johan Lim* (2019). Fixed support positive-definite modification of covariance matrix estimators via linear shrinkage. Journal of Multivariate Analysis 171:234-249. Link
[6] Young-Geun Choi, Wei-Yann Tsai, & Myunghee Cho Paik* (2019). Generalized class of test statistic for testing quasi-independence in left-truncated and right-censored data. Statistica Sinica 29(2):789-808. Link
[5] Young-Geun Choi, Johan Lim* and Sujung Choi (2019). High-dimensional Markowitz portfolio optimization problem: Empirical comparison of covariance matrix estimators. Journal of Statistical Computation and Simulation 89(7):1278-1300. Link
[4] Yongchan Kwon, Young-Geun Choi, Taesung Park, Andreas Ziegler, & Myunghee Cho Paik* (2017). Generalized estimating equations with stabilized working correlation structure. Computational Statistics & Data Analysis 106:1–11. Link
[3] Young-Geun Choi, Chi Tim Ng, and Johan Lim* (2017). Regularized LRT for large scale covariance matrices: One sample problem. Journal of Statistical Planning and Inference 180:108–123. Link
[28] Seong Rae Kim, Young-Geun Choi, and Seong Jin Jo* (2025). Smoking cessation, weight change, and risk of hidradenitis suppurativa: A nationwide population-based cohort study. Journal of the American Academy of Dermatology 93(4): 1113-1116. Link
[27] Junseok Park†, Sungjin Woo†, Young-Geun Choi†, Hoyoung Park, ..., Hyunsun Park,* and Seong-Joon Koh* (2024). Antibiotic Usage within the First Year of Life Has a Protective Effect against Ulcerative Colitis in South Korea: A Nationwide Cohort Study. Digestive and Liver Disease 57(2):616-623. Link
[26] Seong Rae Kim, Young-Geun Choi, and Seong Jin Jo (2024). Smoking cessation and risk of hidradenitis suppurativa development. JAMA Dermatology 160(10):1056-1065. Link
[25] Seong Rae Kim, Young-Geun Choi, and Seong Jin Jo (2024). Duration of smoking cessation for the prevention of psoriasis vulgaris and palmoplantar pustulosis. British Journal of Dermatology, in press. Link
[24] Seong Rae Kim, Young-Geun Choi, and Seong Jin Jo (2024). Effect of smoking cessation on psoriasis vulgaris, palmoplantar pustulosis and generalized pustular psoriasis. British Journal of Dermatology 191(2): 225-232. Link
[22] Jeeyeon Lee, Andrew Won Jun Yang, Liam Il-Young Chung, Jisang Yu, Yunjoo Lee, Hye Sung Kim, Hyun Joon Shin, Young-Geun Choi, Ankit Bharat, and Young Kwang Chae* (2023). A Comprehensive Landscape of De Novo Malignancy After Double Lung Transplantation. Transplant International 36:11552. Link
[19] Yo Han Lee, Hyun-Hee Heo, Hyerim Noh#, Deok Hyun Jang, Young-Geun Choi*, Won Mo Jang*, and Jin Yong Lee (2023). Patterns and trends in factors associated with affective and cognitive risk perceptions of COVID-19. PLoS ONE 18(6): e0280779. Link
[17] Jungyoon Ohn, Young-Geun Choi, Jieun Yun, Seong Jin Cho* (2022). Identifying patients with deteriorating generalized pustular psoriasis: Development of a prediction model. The Journal of Dermatology 49(7):675-681. Link
[16] Hyerim Noh†#, Jongseong Lee†, Ronald Chow†, Jihui Lee, Charles B. Simone II, Hyun Joon Shin, and Young-Geun Choi* (2022). The prognostic role of anticoagulants in COVID-19 patients: National COVID-19 cohort in South Korea. Annals of Palliative Medicine 11(4):1317-1325. Link
[15] Hyun Joon Shin†, Ronald Chow†, Hyerim Noh†#, Jongseong Lee, Jihui Lee, Charles B. Simone II, and Young-Geun Choi* (2022). The association between immunosuppressants use and COVID-19 adverse outcomes: National COVID-19 cohort in South Korea. Annals of Palliative Medicine 11(4):1308-1316. Link
[14] Ronald Chow†, Jihui Lee†, Hyerim Noh†#, Jongseong Lee, Charles B. Simone II, Hyun Joon Shin*, and Young-Geun Choi* (2022). The association between statin and Covid-19 adverse outcome: National COVID-19 cohort in South Korea. Annals of Palliative Medicine 11(4):1294-1307. Link
[11] Leonard Chiu†, Chun-Han Lo, Max Shen, Nicholas Chiu, Rahul Aggarwal, Jihui Lee, Young-Geun Choi, Henry Lam, Elizabeth Horn Prsic, Ronald Chow*, Hyun Joon Shin* (2021). Colchicine use in patients with COVID-19: A systematic review and meta-analysis, PLoS ONE 16(12): e0261358. Link
[10] Ronald Chow, James Im, Nicholas Chiu, Leonard Chiu, Rahul Aggarwal, Jihui Lee, Young-Geun Choi, Elizabeth Horn Prsic, and Hyun Joon Shin* (2021). The protective association between statins use and adverse outcomes among COVID-19 patients: A systematic review and meta-analysis, PLoS ONE 16(6): e0253576. Link
[2] Huy Truong Nguyen, Dong-Kyu Lee, Young-Geun Choi et al. (2016). A 1H NMR-based metabolomics approach to evaluate the geographical authenticity of herbal medicine and its application in building a model effectively assessing the mixing proportion of intentional admixtures: A case study of Panax ginseng. Journal of Pharmaceutical and Biomedical Analysis 124:120–128. Link
[1] Jung A Um, Young-Geun Choi, Dong-Kyu Lee, et al. (2013). Discrimination between genetically identical peony roots from different regions of origin based on 1H-nuclear magnetic resonance spectroscopy-based metabolomics: determination of the geographical origins and estimation of the mixing proportions of blended. Analytical and Bioanalytical Chemistry 405(23):7523–7534. Link
Eun-Kyoung Lee# and Young-Geun Choi* (2025). A comparison study of weighting-based estimators for average treatment effects on the treated in case of rare exposure. Korean Journal of Applied Statistics 38(1):1-12. Link
Young-Geun Choi and Donghyeon Yu* (2019). Causal inference from nonrandomized data: Key concepts and recent trends. Korean Journal of Applied Statistics 32(2): 173–185. Link
Causal inference for positive-unlabeled treatments (w/ Youjin Lee)
Contextual bandits with latent outcomes
Young-Geun Choi, Taehoon Lee, Junghyun Namkung, and Philghyun Kang. (2019). Method and Apparatus for Cyclic Time Series Data Feature Extraction. Application number 10-2019-0027851 (KR).