Un-update Bayesian models to their prior-to-data state

As posteriors are priors that have been updated after observing some data, the goal of this function is to un-update the posteriors to obtain models representing the priors. These models can then be used to examine the prior predictive distribution, or to compare priors with posteriors.

This function in used internally to compute Bayes factors.

Usage

unupdate(model, verbose = TRUE, ...)

# S3 method for stanreg
unupdate(model, verbose = TRUE, ...)

# S3 method for brmsfit
unupdate(model, verbose = TRUE, ...)

# S3 method for brmsfit_multiple
unupdate(model, verbose = TRUE, newdata = NULL, ...)

# S3 method for blavaan
unupdate(model, verbose = TRUE, ...)

Arguments

model

A fitted Bayesian model.

verbose

Toggle warnings.

...

Not used

newdata

List of data.frames to update the model with new data. Required even if the original data should be used.

Value

A model un-fitted to the data, representing the prior model.