1\name{linesHyperb.lm} 2\alias{linesHyperb.lm} 3\title{Plot Confidence or Prediction Hyperbolas around a Regression Line} 4\description{ 5 Add confidence/prediction hyperbolas for \eqn{y(x_0)} 6 to a plot with data or regression line. 7} 8\usage{ 9linesHyperb.lm(object, c.prob=0.95, confidence=FALSE, 10 k=if (confidence) Inf else 1, 11 col=2, lty=2, do.abline=TRUE) 12} 13\arguments{ 14 \item{object}{result of \code{\link{lm}(.)}.} 15 \item{c.prob}{coverage probability in \eqn{(0,1)}.} 16 \item{confidence}{logical; if true, do (small) confidence band, else, 17 realistic prediction band for the mean of \code{k} observations.} 18 \item{k}{integer or \code{Inf}; assume \code{k} future observations; 19 \code{k = Inf} corresponds to confidence intervals (for y).} 20 \item{col, lty}{attributes for the \code{\link{lines}} to be drawn.} 21 \item{do.abline}{logical; if true, the regression line is drawn as well.} 22} 23\note{ 24 With \code{\link{predict.lm}(*, interval=)} is available, 25 this function \code{linesHyperb.lm} is only slightly more general for 26 its \code{k} argument. 27} 28\author{Martin Maechler, Oct 1995} 29\seealso{\code{\link{predict.lm}(*, interval=)} optionally computes 30 prediction or confidence intervals.} 31\examples{ 32data(swiss) 33 plot(Fertility ~ Education, data = swiss) # the data 34(lmS <- lm(Fertility ~ Education, data = swiss)) 35linesHyperb.lm(lmS) 36linesHyperb.lm(lmS, conf=TRUE, col="blue") 37} 38\keyword{regression} 39\keyword{aplot} 40