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When I include a control=list() statement in brms running in RStudio, the model compiles but fails to sample with the following error
SAMPLING FOR MODEL ‘ded7652ad4617eb0e215a91c68d31580’ NOW (CHAIN 1).
 “Error in sampler$call_sampler(args_list[[i]]) : "
 " VECTOR_ELT() can only be applied to a ‘list’, not a ‘symbol’”
error occurred during calling the sampler; sampling not done
format_code(like_this, if_applicable) Here's the code and it runs when I comment out the control statement with "#" form_prior1 <- get_prior(overall_6hr ~ lAge + lBMI + (1|Gender), data=HK_dat2, family=lognormal() ) form_mod1 <- brm(overall_6hr ~ lAge + lBMI + (1|Gender), data=HK_dat2, prior = form_prior1, control = list(adapt_delta = 0.95), family=lognormal(), warmup=3500, chains=2, iter=6000 ) I just updated to Big Sur 11.5.1. The toolchain is fine since the model compiles and runs without the control statement. Thanks in advance for any insights.