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Describe brms model results

Usage

# S3 method for class 'brmsfit'
apa(
  obj,
  term,
  trans = NULL,
  digits = 2,
  eff.size = FALSE,
  eff.size.type = "r",
  nsamples = 100,
  ci.type = "HPDI",
  ...
)

Arguments

obj

model object from brms::brm

term

model term to describe

trans

an optional function to transform the results to another scale (default: NULL)

digits

number of digits in the output

eff.size

string describing how to compute an effect size (currently, either 'fe_to_all', 'part_fe', or 'part_fe_re')

eff.size.type

type of the effect size ('r' or 'r2')

nsamples

number of samples to use for the effect size computations

ci.type

type of intervals to use (currently, all that is not HPDI is treated as ETI using bayestestR::eti)

...

other parameters passed to format_results

Value

A character result reporting the posterior mean coefficient, its 95% interval, and optionally an effect-size estimate.

Examples

# \donttest{
if (requireNamespace("brms", quietly = TRUE) &&
    requireNamespace("bayestestR", quietly = TRUE)) {
  # Generate sample data
  set.seed(42)
  x <- seq(-1, 1, length.out = 30)
  y <- 1 + 2 * x + rnorm(30, sd = 0.5)
  
  # Fit a Bayesian regression model
  fit <- brms::brm(y ~ x, data = data.frame(x, y), backend = "rstan",
                   chains = 1, cores = 1, iter = 500, seed = 42, refresh = 0)
  print(apa(fit, "x"))
  
  # Convert x to another scale for output
  print(apa(fit, "x", trans = function(val) val + 5))
}
#> Compiling Stan program...
#> Error in .fun(model_code = .x1): Boost not found; call install.packages('BH')
# }