\name{gcv}
\alias{gcv}
\title{
Compute generalized cross-validation statistic.
}
\usage{
gcv(x, \dots)
}
\arguments{
  \item{x, \dots}{Arguments passed on to \code{\link{locfit}} or
    \code{\link{locfit.raw}}.}
}
\description{
  The calling sequence for \code{gcv} matches those for the
  \code{\link{locfit}} or \code{\link{locfit.raw}} functions.
  The fit is not returned; instead, the returned object contains
  Wahba's generalized cross-validation score for the fit.

  The GCV score is exact (up to numerical roundoff) if the
  \code{ev="data"} argument is provided. Otherwise, the residual
  sum-of-squares and degrees of freedom are computed using locfit's
  standard interpolation based approximations.

  For likelihood models, GCV is computed uses the deviance
  in place of the residual sum of squares. This produces useful
  results but I do not know of any theory validating
  this extension.
}

\seealso{
  \code{\link{locfit}},
  \code{\link{locfit.raw}},
  \code{\link{gcvplot}}
}

\keyword{htest}
% Converted by Sd2Rd version 0.2-a5.