Rstan meanfield produces a parameter called lp__.1

When running variational inference (meanfield) via rstan, it seems to produce a strange parameter called lp__.1 in addition to the ordinary lp__ parameter. A user reported this issue on the brms github page ( and I want to make sure whether this is intentional before I try to fix it from the brms side.

It is probably a bug in rstan.

Although that “ordinary” lp__ is currently just zeros when using advi. In the future there will be lp__ and lq__ with proper values.

My current problem with lp__.1 (whereever this comes from) is that it appears in stanfit@sim$samples, but not in stanfit@sim$fnames_oi.