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\name{plot.scan.test}
\alias{plot.scan.test}
\alias{as.im.scan.test}
\title{
Plot Result of Scan Test
}
\description{
Computes or plots an image showing the
likelihood ratio test statistic for the scan test,
or the optimal circle radius.
}
\usage{
\method{plot}{scan.test}(x, \dots, what=c("statistic", "radius"),
do.window = TRUE)
\method{as.im}{scan.test}(X, \dots, what=c("statistic", "radius"))
}
\arguments{
\item{x,X}{
Result of a scan test. An object of class \code{"scan.test"}
produced by \code{\link{scan.test}}.
}
\item{\dots}{
Arguments passed to \code{\link[spatstat.geom]{plot.im}} to control the appearance
of the plot.
}
\item{what}{
Character string indicating whether to produce an image of the
(profile) likelihood ratio test statistic (\code{what="statistic"},
the default) or an image of the optimal value of circle radius
(\code{what="radius"}).
}
\item{do.window}{
Logical value indicating whether to plot the original window
of the data as well.
}
}
\details{
These functions extract, and plot, the spatially-varying value
of the likelihood ratio test statistic which forms the basis of
the scan test.
If the test result \code{X} was based on circles of
the same radius \code{r}, then \code{as.im(X)} is a pixel image
of the likelihood ratio test statistic as a function of the
position of the centre of the circle.
If the test result \code{X} was based on circles of
several different radii \code{r}, then \code{as.im(X)} is a pixel image
of the profile (maximum value over all radii \code{r})
likelihood ratio test statistic as a function of the
position of the centre of the circle, and
\code{as.im(X, what="radius")} is a pixel image giving
for each location \eqn{u} the value of \code{r} which maximised
the likelihood ratio test statistic at that location.
The \code{plot} method plots the corresponding image.
}
\value{
The value of \code{as.im.scan.test} is a pixel image (object of
class \code{"im"}). The value of \code{plot.scan.test} is \code{NULL}.
}
\author{\adrian
and \rolf
}
\seealso{
\code{\link{scan.test}},
\code{\link{scanLRTS}}
}
\examples{
online <- interactive()
Nsim <- if(online) 19 else 2
r <- if(online) seq(0.04, 0.1, by=0.01) else c(0.05, 0.1)
a <- scan.test(redwood, r=r, method="poisson", nsim=Nsim)
plot(a)
as.im(a)
plot(a, what="radius")
}
\keyword{htest}
\keyword{spatial}
|
