Research

I am a PhD student in Statistics at Texas A&M, advised by Valen E. Johnson. My dissertation is about estimating latent quantities you cannot observe directly, when the measurements you do have are imperfect.

Dissertation (in progress).

Chapter I — Prevalence without a gold standard.
Prevalence and diagnostic accuracy are estimated from imperfect tests and heterogeneous study designs. We characterize when those parameters are identified, then estimate them with Bayesian latent-class and latent-severity models, checked by parameter-recovery simulations.

Chapter II — Cost burden.
Prevalence is an intermediate. The target is a distribution over economic loss, obtained by propagating the Chapter I posterior together with uncertainty in population and cost inputs.

Selected work

Identifiability under heterogeneous diagnostic designs
Rank, null-space, and design-structure arguments for when prevalence and accuracy are uniquely recoverable. States the designs that identify the target and the sparse or single-test designs that do not. In progress.
Latent class model with a continuous severity variable, compared with a conditional-independence baseline. MCMC with data augmentation; parameter-recovery study; reanalysis of the Strongyloides stool and serology data (Joseph et al., 1995).
Uncertainty propagation for cost burden
Maps the prevalence posterior through population and unit-cost inputs to a distribution over economic loss. Decomposes which source of uncertainty moves the tail. In progress.
Analyses of three public experiments: Cookie Cats, the Udacity free-trial screener, and the Upworthy archive. Each defines the metric, checks the design, and estimates the treatment effect.

Experience

Doctoral researcher

2022 - present
Department of Statistics, Texas A&M University
  • Advisor: Valen E. Johnson.
  • Identifiability and Bayesian estimation for latent disease status without a gold standard.
  • Uncertainty propagation from prevalence into a distribution over cost burden.

Instructor, STAT 211 - Principles of Statistics I

Fall 2026
Department of Statistics, Texas A&M University
  • Undergraduate probability, estimation, testing, regression, and computation in R.

PhD statistics and data science intern

Summer 2025
Lubrizol Corporation, Wickliffe, OH
  • Credible intervals for predictive models, so uncertainty was attached to the forecast rather than reported separately.
  • Repeatability and reproducibility studies to quantify measurement variability for product validation.
  • Predictive models from chemical composition to transmission-fluid performance.

Biostatistics research assistant

Aug 2021 - May 2023
Institute of Biosciences and Technology, Texas A&M University (Kurt Zhang lab)
  • High-dimensional regression and clustering on DNA methylation data.
  • NHANES analysis of dietary risk factors for hypertension in pregnancy.
  • Developed the R package nhanesGraph for searching public-use continuous NHANES files and downloading them from the current CDC XPT URLs, 1999-2000 through August 2021-August 2023. Not an official CDC tool.
  • Analysis contributed to peer-reviewed papers listed below.

Publications

Collaborative papers. Role on each paper is listed after the citation. Dissertation chapters are in preparation and are not listed as publications.

  • Prevalence study in Cameroon identifies Brucella abortus as the endemic Brucella species in livestock
  • Guela, G.K., Laine, C.G., Gontao, P., Gomsu Dada, C.O., Abiba, H., Desire, D.P., Mbacham, W., Garcia-Gonzalez, D., Vection, S., Gillece, J.D., Kim, M., Johnson, V.E., Foster, J.T., Wade, A., Arenas-Gamboa, A.M.
    Nature Communications 16, 11600 (2025). Role - formal analysis, visualization, writing review and editing.
  • Epigenome-wide analysis of aging effects on liver regeneration
  • Wang, J., Zhang, W., Liu, X., Kim, M., Ke, Z., Tsai, R.
    BMC Biology 21, 30 (2023). Role - statistical analysis.
  • Maternal one-carbon supplement reduced the risk of non-alcoholic fatty liver disease in male offspring
  • Peng, H., Xu, H., Wu, J., Li, J., Wang, X., Liu, Z., Kim, M., Jeon, M.S., Zhang, K.K., Xie, L.
    Nutrients 14(12), 2545 (2022). Role - statistical analysis.