Using brms functions for my adjusted Stan model

Interfaces brms
1

Hi I’ve been using brms for one of project. I had to take the code and rewrite it for performance reasons. Just wondering if was possible to get the Stan fit object back into a form to use all the wonderful brms plotting and other utility functions?

2

Yes, you can use the empty = TRUE argument in brms::brm to initialise a brmsfit object, and then fill its fit slot with your rstan / cmdstanr output, followed by a call to the brms function rename_pars. See that function’s documentation for an example: Rename parameters in brmsfit objects — rename_pars • brms

EDIT: If you’re using cmdstanr for fitting the model, you first need to use the function read_csv_as_stanfit to convert the CmdStan CSV output files into a stanfit object that is suitable for the fit slot of the brmsfit object. See the documentation for details.

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