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\name{bootstrap}
\alias{bootstrap}
\alias{samplesplitting}
\alias{jackknife}
\alias{subsampling}
\alias{splithalf}
\title{Sampler Infrastructure for Stability Assessment}
\description{
Sampler objects that provide objects with functionality used by
\code{\link{stabletree}} to generate resampled datasets.
}
\usage{
bootstrap(B = 500, v = 1)
subsampling(B = 500, v = 0.632)
samplesplitting(k = 5)
jackknife(d = 1, maxrep = 5000)
splithalf(B = 500)
}
\arguments{
\item{B}{An integer value specifying the number of resampled datasets.}
\item{k}{An integer value specifying the number of folds in sample-splitting.}
\item{d}{An integer value specifying the number of observations left out in jackknife.}
\item{maxrep}{An integer value specifying the maximum number of resampled datasets allowed, when using jackknife.}
\item{v}{A numeric value between 0 and 1 specifying the fraction of observations in each subsample.}
}
\details{
The sampler functions provide objects that include functionality to generate
resampled datasets used by \code{\link{stabletree}}.
The \code{bootstrap} function provides an object that can be used to generate
\code{B} bootstrap samples by sampling from \code{n} observations with
replacement.
The \code{subsampling} function provides an object that can be used to
generate \code{B} subsamples by sampling from \code{floor(v*n)}
observations without replacement.
The \code{samplesplitting} function provides an object that can be used to
generate \code{k}-folds from \code{n} observations.
The \code{jackknife} function provides an object that can be used to generate
all datasets necessary to perform leave-\code{k}-out jackknife sampling from
\code{n} observations. The number of datasets is limited by \code{maxrep} to
prevent unintended CPU or memory overload by accidently choosing too large
values for \code{k}.
The \code{splithalf} function provides an object that can be used to
generate \code{B} subsamples by sampling from \code{floor(0.5*n)}
observations without replacement. When used to implement the "splithalf"
resampling strategy for measuring the stability of a result via the
\code{\link{stability}} function, the matrix containing the complement
learning samples is generated automatically by \code{\link{stability}}.
}
\seealso{\code{\link{stabletree}}, \code{\link{stability}}}
\examples{
set.seed(0)
## bootstrap sampler
s <- bootstrap(3)
s$sampler(10)
## subsampling
s <- subsampling(3, v = 0.6)
s$sampler(10)
## 5-fold sample-splitting
s <- samplesplitting(5)
s$sampler(10)
## jackknife
s <- jackknife(d = 1)
s$sampler(10)
## splithaf
s <- splithalf(3)
s$sampler(10)
}
\keyword{regression}
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