I would like to raise a question, which is already present but still unsolved here:
After updating rstanarm package to the newest version (2.17.2), I get an error message when trying to load a stanreg object that was fitted with an old version of rstanarm:
Error in if (is.mer(x) && x$stan_function != “stan_gamm4”) return(formula_mer(x, :
missing value where TRUE/FALSE needed
Is there already a workaround?
Thank you in advance!