% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/bayes_R2.R
\name{bayes_R2.brmsfit}
\alias{bayes_R2.brmsfit}
\alias{bayes_R2}
\title{Compute a Bayesian version of R-squared for regression models}
\usage{
\method{bayes_R2}{brmsfit}(
  object,
  resp = NULL,
  summary = TRUE,
  robust = FALSE,
  probs = c(0.025, 0.975),
  ...
)
}
\arguments{
\item{object}{An object of class \code{brmsfit}.}

\item{resp}{Optional names of response variables. If specified, predictions
are performed only for the specified response variables.}

\item{summary}{Should summary statistics be returned
instead of the raw values? Default is \code{TRUE}.}

\item{robust}{If \code{FALSE} (the default) the mean is used as
the measure of central tendency and the standard deviation as
the measure of variability. If \code{TRUE}, the median and the
median absolute deviation (MAD) are applied instead.
Only used if \code{summary} is \code{TRUE}.}

\item{probs}{The percentiles to be computed by the \code{quantile}
function. Only used if \code{summary} is \code{TRUE}.}

\item{...}{Further arguments passed to
\code{\link[brms:posterior_epred.brmsfit]{posterior_epred}},
which is used in the computation of the R-squared values.}
}
\value{
If \code{summary = TRUE}, an M x C matrix is returned
 (M = number of response variables and c = \code{length(probs) + 2})
 containing summary statistics of the Bayesian R-squared values.
 If \code{summary = FALSE}, the posterior draws of the Bayesian
 R-squared values are returned in an S x M matrix (S is the number of draws).
}
\description{
Compute a Bayesian version of R-squared for regression models
}
\details{
For an introduction to the approach, see Gelman et al. (2018)
 and \url{https://github.com/jgabry/bayes_R2/}.
}
\examples{
\dontrun{
fit <- brm(mpg ~ wt + cyl, data = mtcars)
summary(fit)
bayes_R2(fit)

# compute R2 with new data
nd <- data.frame(mpg = c(10, 20, 30), wt = c(4, 3, 2), cyl = c(8, 6, 4))
bayes_R2(fit, newdata = nd)
}

}
\references{
Andrew Gelman, Ben Goodrich, Jonah Gabry & Aki Vehtari. (2018).
  R-squared for Bayesian regression models, \emph{The American Statistician}.
  \code{10.1080/00031305.2018.1549100} (Preprint available at
  \url{https://stat.columbia.edu/~gelman/research/published/bayes_R2_v3.pdf})
}
