$3\mathrm{.}6$: Sometimes, when adjusting Stan model code you may have removed a variable from the model block, but left the declaration in the parameters block. Add such a variable to your model. What do you see from convergence diagnostics $($it may also help you visualise the MCMC chains using mcmc$\_$pairs and mcmc$\_$trace$)?$

Multiple choice $36$ Question $1$

No divergent transitions but some max$\_$treedepth exceedences

Some divergent transitions but no max$\_$treedepth exceedences

No divergent transitions or max$\_$treedepth exceedences, but the chains for the unused variable have clearly not converged

$$

$3\mathrm{.}7$: Use check$\_$syntax$($pedantic $=$ TRUE$),$ would you have been able to detect this problem from the output?

Multiple choice $37$ Question $1$

No

Yes

Unclear