Statistics Department Seminar Series: Christina Knudson, Assistant Professor of Statistics, Department of Mathematics, University of St. Thomas

Abstract: Gelman and Rubin’s (Statist. Sci. 7 (1992) 457–472) convergence diagnostic is one of the most popular methods for terminating a Markov chain Monte Carlo (MCMC) sampler. Since the seminal paper, researchers have developed sophisticated methods for estimating variance of Monte Carlo averages. We show that these estimators find immediate use in the Gelman–Rubin statistic, a connection not previously established in the literature. We incorporate these estimators to upgrade both the univariate and multivariate Gelman–Rubin statistics, leading to improved stability in MCMC termination time. An immediate advantage is that our new Gelman–Rubin statistic can be calculated for a single chain. In addition, we establish a one-to-one relationship between the Gelman–Rubin statistic and effective sample size. Leveraging this relationship, we develop a principled termination criterion for the Gelman–Rubin statistic. Finally, we demonstrate the utility of our improved diagnostic via examples.


Christina Knudson is an assistant professor at the University of St. Thomas, an alumna of the University of Minnesota School of Statistics, and an organizer of the Twin Cities chapter of R Ladies. She researches likelihood-based inference for generalized linear mixed models and termination rules for Markov chain Monte Carlo. She is the creator and author of R packages glmm and stableGR.

https://cknudson.com/