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\name{points.segmented}
\alias{points.segmented}
%- Also NEED an '\alias' for EACH other topic documented here.
\title{
Points method for segmented objects
}
\description{
Takes a fitted \code{segmented} object returned by \code{segmented()} and adds
on the current plot the joinpoints of the fitted broken-line relationships.
}
\usage{
\method{points}{segmented}(x, term, interc = TRUE, link = TRUE, rev.sgn=FALSE,
transf=I, .vcov=NULL, .coef=NULL, const=0, v=TRUE, ...)
}
%- maybe also 'usage' for other objects documented here.
\arguments{
\item{x}{
an object of class \code{segmented}.
}
\item{term}{
the segmented variable of interest. It may be unspecified when there is a single segmented variable.
}
\item{interc}{
If \code{TRUE} the computed joinpoints include the model intercept (if it exists).
}
\item{link}{
when \code{TRUE} (default), the fitted joinpoints are plotted on the link scale
}
\item{rev.sgn}{
when \code{TRUE}, the fitted joinpoints are plotted on the `minus' scale
of the current \code{term} variable. This is useful when a null-constraint
has been set on the last slope.
}
\item{transf}{
A possible function to convert the fitted values before plotting.
}
\item{.vcov}{ The \emph{full} covariance matrix of estimates. If unspecified (i.e. \code{NULL}), the covariance matrix is computed internally by \code{vcov()}.}
\item{.coef}{ The regression parameter estimates. If unspecified (i.e. \code{NULL}), it is computed internally by \code{coef(x)}.}
\item{const}{ A constant to be added (on the y-scale) to the values before transforming and plotting.}
\item{v}{logical. If \code{TRUE}, vertical lines at the breakpoints are also drawn.}
\item{\dots}{
other graphics parameters to pass on to \code{points()} and \code{segments()} (if \code{v=TRUE}).
}
}
\details{
We call 'joinpoint' the plane point having as coordinates the breakpoints (on the x scale) and the fitted values of
the segmented relationship at that breakpoints (on the y scale). \code{points.segmented()} simply adds the fitted
joinpoints on the current plot. This could be useful to emphasize the changes of the piecewise linear relationship.
}
%\value{
%% ~Describe the value returned
%% If it is a LIST, use
%% \item{comp1 }{Description of 'comp1'}
%% \item{comp2 }{Description of 'comp2'}
%% ...
%}
%\references{
%% ~put references to the literature/web site here ~
%}
%\author{
%% ~~who you are~~
%}
%\note{
%% ~~further notes~~
%}
%% ~Make other sections like Warning with \section{Warning }{....} ~
\seealso{ \code{\link{plot.segmented}} to plot the fitted segmented lines. }
\examples{
\dontrun{
#see examples in ?plot.segmented
}
}
\keyword{ nonlinear }
\keyword{ regression }% __ONLY ONE__ keyword per line
|
