activity
20182026
collaborators

12 papers

stat.ME2026

Bigraphical Matérn-Whittle (BMW) Processes for Fast Inference of Big Multivariate Spatial Data on General Domains

Debangan Dey, Alokesh Manna, Christopher J. Geoga

Large spatial data sets now record many correlated variables at many thousands of locations, often on domains where Euclidean distance misrepresents proximity. The central difficul…

math.NA2026

Linear-cost Polyharmonic Spline Interpolation of Arbitrary Degree

Christopher J. Geoga, Michael O'Neil

We introduce a simple and performant approach for rapidly and accurately performing polyharmonic spline (PHS) interpolation using a combination of the fast multipole method (FMM) f…

stat.AP2026

A Gaussian Process Model of 3D Udder Point Clouds for Teat Length Phenotyping in Dairy Cows

Maria E. Montes, João R. R. Doréa, Christopher J. Geoga

Phenotyping conformation traits is important for dairy cattle breeding and management. Although large-scale phenotyping is possible with 3D imaging technologies, manual annotation…

stat.CO2026

Fast and accurate conditioning for large-scale Gaussian process prediction problems

Samanyu Arora, Christopher J. Geoga

Gaussian Process (GP) models provide a flexible framework for prediction and uncertainty quantification. For most covariance functions, however, exact GP prediction with points…

physics.ao-ph2025

High-Resolution Retrieval of Atmospheric Boundary Layers with Nonstationary Gaussian Processes

Haoran Xiong, Paytsar Muradyan, Christopher J. Geoga

The atmospheric boundary layer (ABL) plays a critical role in governing turbulent exchanges of momentum, heat moisture, and trace gases between the Earth's surface and the free atm…

stat.ME2025

Fast nonparametric spectral density estimation from irregularly sampled data

Christopher J. Geoga, Paul G. Beckman

We introduce a nonparametric spectral density estimator for continuous-time and continuous-space processes measured at fully irregular locations. Our estimator is constructed using…

stat.CO2024

Fast Adaptive Fourier Integration for Spectral Densities of Gaussian Processes

Paul G. Beckman, Christopher J. Geoga

The specification of a covariance function is of paramount importance when employing Gaussian process models, but the requirement of positive definiteness severely limits those use…

math.NA2024

Fast Machine-Precision Spectral Likelihoods for Stationary Time Series

Christopher J. Geoga

We provide in this work an algorithm for approximating a very broad class of symmetric Toeplitz matrices to machine precision in time with applications to f…

stat.ME2022

A Scalable Method to Exploit Screening in Gaussian Process Models with Noise

Christopher J. Geoga, Michael L. Stein

A common approach to approximating Gaussian log-likelihoods at scale exploits the fact that precision matrices can be well-approximated by sparse matrices in some circumstances. Th…

stat.CO2022

Scalable Computations for Nonstationary Gaussian Processes

Paul G. Beckman, Christopher J. Geoga, Michael L. Stein +1

Nonstationary Gaussian process models can capture complex spatially varying dependence structures in spatial datasets. However, the large number of observations in modern datasets…

stat.ME2020

Flexible nonstationary spatio-temporal modeling of high-frequency monitoring data

Christopher J. Geoga, Mihai Anitescu, Michael L. Stein

Many physical datasets are generated by collections of instruments that make measurements at regular time intervals. For such regular monitoring data, we extend the framework of ha…

stat.CO2018

Scalable Gaussian Process Computations Using Hierarchical Matrices

Christopher J. Geoga, Mihai Anitescu, Michael L. Stein

We present a kernel-independent method that applies hierarchical matrices to the problem of maximum likelihood estimation for Gaussian processes. The proposed approximation provide…