Research

Submitted/Under Revision Articles

• Ki, D. and Guntuboyina, A. (2026+) What functions does XGBoost learn? Submitted. [arXiv] [slides] [poster]
  • ICSDS Student Travel Award, Institute of Mathematical Statistics, 2025

Publications

• Ki, D. and Guntuboyina, A. (2026) Totally concave regression. Journal of the American Statistical Association, accepted for publication. [arXiv] [journal] [code] [slides] [poster]
  • KISS Outstanding Student Paper Award, Korean International Statistical Society, 2025
  • IMS Hannan Graduate Student Travel Award, Institute of Mathematical Statistics, 2024
• Ki, D., Fang, B., and Guntuboyina, A. (2024) MARS via LASSO. Annals of Statistics, 52(3), 1102-1126. [arXiv] [journal] [code] [slides]
  • IISA Student Paper Award, International Indian Statistical Association, 2023
  • SFASA Student Travel Award, San Francisco Bay Area Chapter of the American Statistical Association, 2022

• Ki, D. and Park, B. U. (2021) Intrinsic Hölder classes of density functions on Riemannian manifolds and lower bounds to convergence rates. Statistics & Probability Letters, 169, 108959. [journal]

• Han, K. and Ki, D. (2020) Better bootstrapping for approximate homomorphic encryption. In Cryptographer’s Track at the RSA Conference (CT-RSA) (pp. 364–390), Cham: Springer. [proceedings]

Software

• regmdc: R package for fitting nonparametric regression models with mixed derivative constraints. [github]