About

I’m an Assistant Professor in the Statistics Department in the Bailey College of Science and Mathematics at Cal Poly SLO. My work connects statistical methodology for complex structured data with substantive scientific applications. I am interested in time series analysis, model selection, high-dimensional data, and statistical algorithms, and I currently work on biological and ecological applications.

Vita

California Polytechnic State University, San Luis Obispo

Assistant Professor | 2023-present

University of California, Santa Barbara

Visiting Assistant Professor | 2020-2023

Oregon State University

Ph.D. Statistics | 2020

M.S. Statistics | 2017

Portland State University

Graduate Certificate in Applied Statistics | 2015

Reed College

B.A. Philosophy | 2011

Projects

Selected work in progress, AY25-26. Working titles.

  • Inference for Local Similarity in Nonstationary Time Series via Rolling Correlation, with Application to Assessing Stability in an Estuarine System. This project develops a nonparametric method for detecting localized departures from trend similarity in paired time series. The method is implemented in an R package, validated through large-scale simulation studies, and applied to environmental monitoring data. Collaboration with Emily Bockmon (Chemistry), with student contributors Alea Seifert (Statistics), Emma Hamilton (Applied Mathematics/Statistics), Catherine Mispagel (Statistics), Andres Rocha (Applied Mathematics/Statistics), and Otis Hunt (Statistics).

  • Modeling Variation in Rattlesnake Populations across Geographic and Climatic Gradients with Multilevel Functional Regression. This project uses a hierarchical functional regression framework to model daily physiological body temperature curves from individual rattlesnakes in multiple populations across western North America. The project develops methods for estimation at scale – the data comprise over one million hourly observations from hundreds of individuals across nearly twenty sites – and examines how environmental and interannual variation shapes physiological responses. Collaboration with Emily Taylor (Biology) and Haley Moniz (Biology), with student contributors Nicole Yee (Statistics) and Allen Choi (Statistics).

  • Borrowing strength across taxonomic levels for inference of ecological association networks from amplicon sequencing data. This work develops a taxonomy-aware method for estimating ecological association networks from amplicon sequencing data that jointly estimates networks at multiple taxonomic levels and borrows information across levels to improve inference at biologically meaningful resolution. A cross-level consistency penalty in the joint estimation objective allows finer-level signals with strong coarser-level aggregate support to be selected more easily, allowing recovery of network structure below the detection thresholds of standard approaches while reducing false discoveries.

Papers

Recent and current work; see CV for a full publication list. Annotations: co-leads\(^\S\); students\(^\dagger\).

  • C.C. Pawlak, R.J. Kenny, T.D. Ruiz, K. Veerasingam\({^\dagger}\), J.C. Schedler, A. Pineda, G.A. Fricker, T.W. Gillespie, M.K. Ritter, J.M. Yost. Integrating Arborist Records and Remote Sensing to Improve Urban Tree Allometric Equations and Benefit Estimates. In preparation.

  • S.J. Weaver, E.H. Barnes\(^{\dagger}\), A. Ramos\(^{\dagger}\), K. Brock, E. Odberg, J. Chung, T.D. Ruiz, E.N. Taylor. Cutaneous evaporative water loss is invariably low among Mojave desert lizard species. In preparation.

  • E.V. Satterthwaite\(^\S\), T.D. Ruiz\(^\S\), N.V. Patin, M.N. Alksne, L. Thomas, J. Dinasquet, R.H. Lampe, N.A. Patrick\(^\dagger\), K.G. Chan\(^\dagger\), A.E. Allen, S. Baumann-Pickering, B.X. Semmens (2026). Microbial and small plankton environmental DNA predicts density of blue, fin, and humpback whales in the southern California bight. PLOS One. [paper] [code] [data]

  • T. D. Ruiz, S. Bhattacharyya, S. C. Emerson (2025). Sparse estimation of parameter support sets for generalized vector autoregressions by resampling and model aggregation. Journal of Statistical Computation and Simulation. [paper] [code] [preprint]

  • H. A. Moniz, J. H. Buck, H. L. Crowell, S. M. Goetz, T. D. Ruiz, S. M. Boback, E. N. Taylor (2024). High thermal quality rookeries facilitate high thermoregulatory accuracy in pregnant female rattlesnakes. Journal of Thermal Biology. [paper] [code] [data]

Courses

Recent and upcoming courses; see CV for full teaching record.

  • [STAT3530] Applied linear models
  • [STAT545] Applied stochastic processes
  • [STAT425] Probability theory

Students

Current students, in alphabetical order by graduation year. See CV for past students.

Thesis

  • Emi Degembe, B.S/M.S. Statistics 2027
  • Nicole Yee, B.S/M.S. Statistics 2027
  • Jose Garcia, B.S/M.S. Statistics 2026
  • Alex Yuan, B.S./M.S. Statistics 2026

Research

  • Otis Hunt, B.S./M.S. Statistics 2028
  • Barbara Ibrahim, B.S./M.S. Statistics 2028
  • Catherine Mispagel, B.S./M.S. Statistics 2028
  • Carson Neubert, B.S./M.S. Statistics 2028
  • Emma Hamilton, B.S./M.S. Statistics 2027
  • Alea Seifert, B.S./M.S. Statistics 2027
  • Kaviya Veerasingam, B.S. Statistics 2027
  • Allen Choi, B.S./M.S. Statistics 2026
  • Andres Rocha, B.S. Statistics/B.S. Applied Mathematics 2026