brms predictions as draws

Create predictions using brms functions and convert them into draws format

Usage

predictions_as_draws(
  x,
  predict_fn,
  prediction_names = NULL,
  warn_dims = getOption("priorsense.warn", TRUE),
  ...
)

Arguments

x

brmsfit object

predict_fn

function for predictions

prediction_names

optional names of the predictions

warn_dims

throw a warning when coercing predict_fn's output from 3 margins to 2 margins?

...

further arguments passed to predict_fn

Value

draws array of predictions

Examples

# \dontrun{
library(brms)
#> Loading required package: Rcpp
#> Loading 'brms' package (version 2.23.1). Useful instructions
#> can be found by typing help('brms'). A more detailed introduction
#> to the package is available through vignette('brms_overview').
#> 
#> Attaching package: ‘brms’
#> The following object is masked from ‘package:stats’:
#> 
#>     ar

if ("log_prior_draws.brmsfit" %in% methods(log_prior_draws) &&
    ("log_lik_draws.brmsfit" %in% methods(log_lik_draws))) {
  fit <- brm(
    yield ~ N * P * K,
    data = npk,
    prior = prior(normal(0, 1), class = "b"),
    refresh = 0
  )

  powerscale_sensitivity(
      fit,
      variable = "_pred",
      prediction = function(x) predictions_as_draws(
                                 x, brms::posterior_epred
                               )
  )
}
#> Compiling Stan program...
#> Start sampling
#> Error in prediction(x$fit, ...): unused argument (separator = "_")
# }