My research focuses on reliable inference in nonstandard settings with, for example, complex dependence, parameters near the boundary, or singular Fisher information. I develop theory, methods, and computationally efficient software implementing the proposed methods. I regularly collaborate with researchers in biomedicine, psychology, and economics.

Articles

Theory and methods

Likelihood-based inference with separable correlation matrices. K.O. Ekvall.
Submitted
arXiv | R package | Code

Universal inference for variance components. Y. Zhang, K.O. Ekvall, and A.J. Molstad.
Stat, 2026
Stat | arXiv | Code

Uniform inference in linear mixed models. K.O. Ekvall and M. Bottai.
Biometrika, 2026
Bmk | arXiv | Supplement | Code

Fast and reliable confidence intervals for a variance component. Y. Zhang, K.O. Ekvall, and A.J. Molstad.
Biometrika, 2025
Bmk | arXiv | Supplement | Code | R package

Direct covariance matrix estimation with compositional data. A.J. Molstad, K.O. Ekvall, and Piotr M. Suder.
Electronic Journal of Statistics, 2024
EJS | arXiv | Supplement

Concave likelihood-based regression with finite-support response variables. K.O. Ekvall and M. Bottai.
Biometrics, 2023
Bmc | arXiv | Supplement | Code

Confidence regions near singular information and boundary points with applications to mixed models. K.O. Ekvall and M. Bottai.
Annals of Statistics, 2022
AoS | pdf | arXiv | Supplement | Code

Targeted principal components regression. K.O. Ekvall.
Journal of Multivariate Analysis, 2022
JMVA | arXiv | Code | R package

Mixed-type multivariate response regression with covariance estimation. K.O. Ekvall and A.J. Molstad.
Statistics in Medicine, 2022
SiM | arXiv | Supplement | R package

Convergence analysis of a collapsed Gibbs sampler for Bayesian vector autoregressions. K.O. Ekvall and G.L. Jones.
Electronic Journal of Statistics, 2021
EJS | arXiv | Code

Consistent maximum likelihood estimation using subsets with applications to multivariate mixed models. K.O. Ekvall and G.L. Jones.
Annals of Statistics, 2020
AoS | arXiv | Supplement

Markov chain Monte Carlo. K.O. Ekvall and G.L. Jones.
Wiley StatsRef, 2019
Wiley | pdf

Applications

Brief stimulus changes signaling extinction enhance resurgence. C.N. Martinez-Perez, J. Williams, C.M. Ritchey, T. Kuroda, K.O. Ekvall, and C.A. Podlesnik.
Submitted

Mediation by thyroid hormone in the relationships between gestational exposure to methylmercury and birth size. K. Gustin, K.O. Ekvall, M. Barman, B. Jacobsson, A. Sandin, A.S. Sandberg, A.E. Wold, M. Vahter, and M. Kippler.
Exposure and Health, 2023
EaH