R: (Deprecated) Extract Posterior Samples

posterior_samples.brmsfit {brms}

R Documentation

(Deprecated) Extract Posterior Samples

Description

Extract posterior samples of specified parameters. The posterior_samples method is deprecated. We recommend using the more modern and consistent as_draws_* extractor functions of the posterior package instead.

Usage

## S3 method for class 'brmsfit'
posterior_samples(
  x,
  pars = NA,
  fixed = FALSE,
  add_chain = FALSE,
  subset = NULL,
  as.matrix = FALSE,
  as.array = FALSE,
  ...
)

posterior_samples(x, pars = NA, ...)

Arguments

`x`	An `R` object typically of class `brmsfit`
`pars`	Names of parameters for which posterior samples should be returned, as given by a character vector or regular expressions. By default, all posterior samples of all parameters are extracted.
`fixed`	Indicates whether parameter names should be matched exactly (`TRUE`) or treated as regular expressions (`FALSE`). Default is `FALSE`.
`add_chain`	A flag indicating if the returned `data.frame` should contain two additional columns. The `chain` column indicates the chain in which each sample was generated, the `iter` column indicates the iteration number within each chain.
`subset`	A numeric vector indicating the rows (i.e., posterior samples) to be returned. If `NULL` (the default), all posterior samples are returned.
`as.matrix`	Should the output be a `matrix` instead of a `data.frame`? Defaults to `FALSE`.
`as.array`	Should the output be an `array` instead of a `data.frame`? Defaults to `FALSE`.
`...`	Arguments passed to individual methods (if applicable).

Value

A data.frame (matrix or array) containing the posterior samples.

Examples

## Not run: 
fit <- brm(rating ~ treat + period + carry + (1|subject), 
           data = inhaler, family = "cumulative")

# extract posterior samples of population-level effects 
samples1 <- posterior_samples(fit, pars = "^b")
head(samples1)

# extract posterior samples of group-level standard deviations
samples2 <- posterior_samples(fit, pars = "^sd_")
head(samples2)

## End(Not run)