Hi，I recently encountered the error below related to Tail ESS and I adjusted my total number of iterations from 4000 to 5000 and used default warm-up, still couldn’t get rid of the warning. Any suggestions on what might cause this warning?
hash mismatch so recompiling; make sure Stan code ends with a blank line Warning messages: 1: In system(paste(CXX, ARGS), ignore.stdout = TRUE, ignore.stderr = TRUE) : '-E' not found 2: Tail Effective Samples Size (ESS) is too low, indicating posterior variances and tail quantiles may be unreliable. Running the chains for more iterations may help. See http://mc-stan.org/misc/warnings.html#tail-ess