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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/boot.iid.R
\name{boot.iid}
\alias{boot.iid}
\title{Demonstrate bootstrapping for iid data}
\usage{
boot.iid(
x = runif(20),
statistic = mean,
m = length(x),
mat = matrix(1:2, 2),
widths = rep(1, ncol(mat)),
heights = rep(1, nrow(mat)),
col = c("black", "red", "bisque", "red", "gray"),
cex = c(1.5, 0.8),
main,
...
)
}
\arguments{
\item{x}{a numerical vector (the original data).}
\item{statistic}{A function which returns a value of the statistic of
interest when applied to the data x.}
\item{m}{the sample size for bootstrapping (\eqn{m}-out-of-\eqn{n} bootstrap)}
\item{mat, widths, heights}{arguments passed to \code{\link{layout}} to set the
layout of the two graphs}
\item{col}{a character vector of length 5 specifying the colors of: points of
original data, points for the sunflowerplot, rectangles of the histogram,
the density line, and the rug.}
\item{cex}{a numeric vector of length 2: magnification of original data
points and the sunflowerplot points.}
\item{main}{a character vector of length 2: the main titles of the two
graphs.}
\item{...}{other arguments passed to \code{\link{hist}}}
}
\value{
A list containing \item{t0 }{ The observed value of 'statistic'
applied to 'x'.} \item{tstar }{Bootstrap versions of the 'statistic'.}
}
\description{
Use a sunflower scatter plot to illustrate the results of resampling, and a
histogram to show the distribution of the statistic of interest.
}
\details{
This is actually a very naive version of bootstrapping but may be useful for
novices. By default, the circles denote the original dataset, while the red
sunflowers (probably) with leaves denote the points being resampled; the
number of leaves just means how many times these points are resampled, as
bootstrap samples \emph{with} replacement. The x-axis is the sample values,
and y-axis is the indices of sample points.
The whole process has illustrated the steps of resampling, computing the
statistic and plotting its distribution based on bootstrapping.
}
\note{
The maximum times of resampling is specified in
\code{ani.options('nmax')}.
}
\references{
Examples at \url{https://yihui.org/animation/example/boot-iid/}
There are many references explaining the bootstrap and its
variations.
Efron, B. and Tibshirani, R. (1993) \emph{An Introduction to the
Bootstrap}. Chapman & Hall.
}
\seealso{
\code{\link{sunflowerplot}}
}
\author{
Yihui Xie
}
|
