The R Project SVN R

\name{weighted.mean}
\title{Weighted Arithmetic Mean}
\usage{
weighted.mean(x, w, na.rm=FALSE)
}
\alias{weighted.mean}
\arguments{
\item{x}{a numeric vector containing the values
whose mean is to be computed.}
\item{w}{a vector of weights the same length as \code{x} giving
the weights to use for each element of \code{x}.}
\item{na.rm}{a logical value indicating whether \code{NA}
values in \code{x} should be stripped before the computation proceeds.}
}
\description{
  Computed a weighted mean of a numeric vector.
}
\details{
If \code{w} is missing then all elements of \code{x} are
given the same weight.

Missing values in \code{w} are not handled.
}
\seealso{
\code{\link{mean}}
}
\examples{
## GPA from Siegel 1994
wt<- c(5/15,5/15,4/15,1/15)
x <- c(3.7,3.3,3.5,2.8)
xm <- weighted.mean(x,wt)
}
\keyword{univar}