Add prior values to Stan input for baggr
set_prior_val(target, name, prior, p = 1)
list object (Stan input) to which prior will be added
prior name, like hypermean
, hypersd
, hypercor
one of prior distributions allowed by baggr like normal
number of repeats of the prior, i.e. when P i.i.d. priors are set for P dimensional parameter as in "mu & tau" type of model