Please share your Stan program and accompanying data if possible.

I am running RStudio and R (3.6.1) on a linux CentOS 7.2 server with 24 cores and 134 GB dedicated RAM. rstanarm (2.18.2) installed. Created stan_lmer model (13 covariates + 10-level grouping variable) on 1.1 M row dataset using 4 chains. Model completed with all Rhats 1.01 or smaller and sufficient ESS.

median(bayes_R2(model)) aborted R session.

Reproducible.

Nathan

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