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+\name{calplot}
+\alias{calplot}
+\alias{calplot.default}
+\alias{calplot.lm}
+\title{Plot calibration graphs from univariate linear models}
+\description{
+ Produce graphics of calibration data, the fitted model as well
+ as confidence, and, for unweighted regression, prediction bands.
+}
+\usage{
+ calplot(object, xlim = c("auto", "auto"), ylim = c("auto", "auto"),
+ xlab = "Concentration", ylab = "Response", alpha=0.05, varfunc = NULL)
+}
+\arguments{
+ \item{object}{
+ A univariate model object of class \code{\link{lm}} or
+ \code{\link[MASS:rlm]{rlm}}
+ with model formula \code{y ~ x} or \code{y ~ x - 1}.
+ }
+ \item{xlim}{
+ The limits of the plot on the x axis.
+ }
+ \item{ylim}{
+ The limits of the plot on the y axis.
+ }
+ \item{xlab}{
+ The label of the x axis.
+ }
+ \item{ylab}{
+ The label of the y axis.
+ }
+ \item{alpha}{
+ The error tolerance level for the confidence and prediction bands. Note that this
+ includes both tails of the Gaussian distribution, unlike the alpha and beta parameters
+ used in \code{\link{lod}} (see note below).
+ }
+ \item{varfunc}{
+ The variance function for generating the weights in the model.
+ Currently, this argument is ignored (see note below).
+ }
+}
+\value{
+ A plot of the calibration data, of your fitted model as well as lines showing
+ the confidence limits. Prediction limits are only shown for models from
+ unweighted regression.
+}
+\note{
+ Prediction bands for models from weighted linear regression require weights
+ for the data, for which responses should be predicted. Prediction intervals
+ using weights e.g. from a variance function are currently not supported by
+ the internally used function \code{\link{predict.lm}}, therefore,
+ \code{calplot} does not draw prediction bands for such models.
+
+ It is possible to compare the \code{\link{calplot}} prediction bands with the
+ \code{\link{lod}} values if the \code{lod()} alpha and beta parameters are
+ half the value of the \code{calplot()} alpha parameter.
+
+}
+\examples{
+data(massart97ex3)
+m <- lm(y ~ x, data = massart97ex3)
+calplot(m)
+}
+\author{
+ Johannes Ranke
+ \email{jranke@uni-bremen.de}
+ \url{http://www.uft.uni-bremen.de/chemie/ranke}
+}
+\keyword{regression}

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