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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/knnreg.R
\name{knnreg}
\alias{knnreg}
\alias{knnregTrain}
\alias{knnreg.formula}
\alias{knnreg.default}
\alias{knnreg.matrix}
\alias{knnreg.data.frame}
\alias{print.knnreg}
\title{k-Nearest Neighbour Regression}
\usage{
knnreg(x, ...)
\method{knnreg}{default}(x, ...)
\method{knnreg}{formula}(formula, data, subset, na.action, k = 5, ...)
\method{knnreg}{matrix}(x, y, k = 5, ...)
\method{knnreg}{data.frame}(x, y, k = 5, ...)
\method{print}{knnreg}(x, ...)
knnregTrain(train, test, y, k = 5, use.all = TRUE)
}
\arguments{
\item{x}{a matrix or data frame of training set predictors.}
\item{...}{additional parameters to pass to \code{knnregTrain}.}
\item{formula}{a formula of the form \code{lhs ~ rhs} where \code{lhs} is
the response variable and \code{rhs} a set of predictors.}
\item{data}{optional data frame containing the variables in the model
formula.}
\item{subset}{optional vector specifying a subset of observations to be
used.}
\item{na.action}{function which indicates what should happen when the data
contain \code{NA}s.}
\item{k}{number of neighbours considered.}
\item{y}{a numeric vector of outcomes.}
\item{train}{matrix or data frame of training set cases.}
\item{test}{matrix or data frame of test set cases. A vector will be
interpreted as a row vector for a single case.}
\item{use.all}{controls handling of ties. If true, all distances equal to
the \code{k}th largest are included. If false, a random selection of
distances equal to the \code{k}th is chosen to use exactly \code{k}
neighbours.}
}
\value{
An object of class \code{knnreg}. See \code{\link{predict.knnreg}}.
}
\description{
$k$-nearest neighbour regression that can return the average value for the
neighbours.
}
\details{
\code{knnreg} is similar to \code{\link[ipred]{ipredknn}} and
\code{knnregTrain} is a modification of \code{\link[class]{knn}}. The
underlying C code from the \code{class} package has been modified to return
average outcome.
}
\examples{
data(BloodBrain)
inTrain <- createDataPartition(logBBB, p = .8)[[1]]
trainX <- bbbDescr[inTrain,]
trainY <- logBBB[inTrain]
testX <- bbbDescr[-inTrain,]
testY <- logBBB[-inTrain]
fit <- knnreg(trainX, trainY, k = 3)
plot(testY, predict(fit, testX))
}
\author{
\code{\link[class]{knn}} by W. N. Venables and B. D. Ripley and
\code{\link[ipred]{ipredknn}} by Torsten.Hothorn
<Torsten.Hothorn@rzmail.uni-erlangen.de>, modifications by Max Kuhn and
Chris Keefer
}
\keyword{multivariate}
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