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authorranke <ranke@5fad18fb-23f0-0310-ab10-e59a3bee62b4>2007-10-01 19:44:04 +0000
committerranke <ranke@5fad18fb-23f0-0310-ab10-e59a3bee62b4>2007-10-01 19:44:04 +0000
commit14a5af60a36071f6a9b4471fdf183fd91e89e1cd (patch)
tree8c845109c3b3e7663b903f3a9d06f7094a4438d8 /man
parent3dec3886b58f73427409d3ef9427c8440420cbc0 (diff)
Moved everything into the trunk directory, in order to enable branching
git-svn-id: http://kriemhild.uft.uni-bremen.de/svn/chemCal@22 5fad18fb-23f0-0310-ab10-e59a3bee62b4
Diffstat (limited to 'man')
-rw-r--r--man/calplot.lm.Rd62
-rw-r--r--man/chemCal-package.Rd17
-rw-r--r--man/din32645.Rd61
-rw-r--r--man/inverse.predict.Rd69
-rw-r--r--man/ipowfunc.Rd33
-rw-r--r--man/lod.Rd83
-rw-r--r--man/loq.Rd77
-rw-r--r--man/massart97ex1.Rd17
-rw-r--r--man/massart97ex3.Rd51
-rw-r--r--man/powfunc.Rd32
10 files changed, 0 insertions, 502 deletions
diff --git a/man/calplot.lm.Rd b/man/calplot.lm.Rd
deleted file mode 100644
index 6f6d584..0000000
--- a/man/calplot.lm.Rd
+++ /dev/null
@@ -1,62 +0,0 @@
-\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.
- }
- \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.
-}
-\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}
diff --git a/man/chemCal-package.Rd b/man/chemCal-package.Rd
deleted file mode 100644
index 4456150..0000000
--- a/man/chemCal-package.Rd
+++ /dev/null
@@ -1,17 +0,0 @@
-\name{chemCal-package}
-\alias{chemCal-package}
-\docType{package}
-\title{
- Calibration functions for analytical chemistry
-}
-\description{
- See \url{../DESCRIPTION}
-}
-\details{
- There is a package vignette located in \url{../doc/chemCal.pdf}.
-}
-\author{
- Author and Maintainer: Johannes Ranke <jranke@uni-bremen.de>
-}
-\keyword{manip}
-}
diff --git a/man/din32645.Rd b/man/din32645.Rd
deleted file mode 100644
index cacbf07..0000000
--- a/man/din32645.Rd
+++ /dev/null
@@ -1,61 +0,0 @@
-\name{din32645}
-\docType{data}
-\alias{din32645}
-\title{Calibration data from DIN 32645}
-\description{
- Sample dataset to test the package.
-}
-\usage{data(din32645)}
-\format{
- A dataframe containing 10 rows of x and y values.
-}
-\examples{
-data(din32645)
-m <- lm(y ~ x, data = din32645)
-calplot(m)
-
-## Prediction of x with confidence interval
-(prediction <- inverse.predict(m, 3500, alpha = 0.01))
-
-# This should give 0.07434 according to test data from Dintest, which
-# was collected from Procontrol 3.1 (isomehr GmbH) in this case
-round(prediction$Confidence,5)
-
-## Critical value:
-(crit <- lod(m, alpha = 0.01, beta = 0.5))
-
-# According to DIN 32645, we should get 0.07 for the critical value
-# (decision limit, "Nachweisgrenze")
-round(crit$x, 2)
-# and according to Dintest test data, we should get 0.0698 from
-round(crit$x, 4)
-
-## Limit of detection (smallest detectable value given alpha and beta)
-# In German, the smallest detectable value is the "Erfassungsgrenze", and we
-# should get 0.14 according to DIN, which we achieve by using the method
-# described in it:
-lod.din <- lod(m, alpha = 0.01, beta = 0.01, method = "din")
-round(lod.din$x, 2)
-
-## Limit of quantification
-# This accords to the test data coming with the test data from Dintest again,
-# except for the last digits of the value cited for Procontrol 3.1 (0.2121)
-(loq <- loq(m, alpha = 0.01))
-round(loq$x,4)
-
-# A similar value is obtained using the approximation
-# LQ = 3.04 * LC (Currie 1999, p. 120)
-3.04 * lod(m,alpha = 0.01, beta = 0.5)$x
-}
-\references{
- DIN 32645 (equivalent to ISO 11843), Beuth Verlag, Berlin, 1994
-
- Dintest. Plugin for MS Excel for evaluations of calibration data. Written
- by Georg Schmitt, University of Heidelberg.
- \url{http://www.rzuser.uni-heidelberg.de/~df6/download/dintest.htm}
-
- Currie, L. A. (1997) Nomenclature in evaluation of analytical methods including
- detection and quantification capabilities (IUPAC Recommendations 1995).
- Analytica Chimica Acta 391, 105 - 126.
-}
-\keyword{datasets}
diff --git a/man/inverse.predict.Rd b/man/inverse.predict.Rd
deleted file mode 100644
index 347d670..0000000
--- a/man/inverse.predict.Rd
+++ /dev/null
@@ -1,69 +0,0 @@
-\name{inverse.predict}
-\alias{inverse.predict}
-\alias{inverse.predict.lm}
-\alias{inverse.predict.rlm}
-\alias{inverse.predict.default}
-\title{Predict x from y for a linear calibration}
-\usage{inverse.predict(object, newdata, \dots,
- ws, alpha=0.05, var.s = "auto")
-}
-\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{newdata}{
- A vector of observed y values for one sample.
- }
- \item{\dots}{
- Placeholder for further arguments that might be needed by
- future implementations.
- }
- \item{ws}{
- The weight attributed to the sample. This argument is obligatory
- if \code{object} has weights.
- }
- \item{alpha}{
- The error tolerance level for the confidence interval to be reported.
- }
- \item{var.s}{
- The estimated variance of the sample measurements. The default is to take
- the residual standard error from the calibration and to adjust it
- using \code{ws}, if applicable. This means that \code{var.s}
- overrides \code{ws}.
- }
-}
-\value{
- A list containing the predicted x value, its standard error and a
- confidence interval.
-}
-\description{
- This function predicts x values using a univariate linear model that has been
- generated for the purpose of calibrating a measurement method. Prediction
- intervals are given at the specified confidence level.
- The calculation method was taken from Massart et al. (1997). In particular,
- Equations 8.26 and 8.28 were combined in order to yield a general treatment
- of inverse prediction for univariate linear models, taking into account
- weights that have been used to create the linear model, and at the same
- time providing the possibility to specify a precision in sample measurements
- differing from the precision in standard samples used for the calibration.
- This is elaborated in the package vignette.
-}
-\note{
- The function was validated with examples 7 and 8 from Massart et al. (1997).
-}
-\references{
- Massart, L.M, Vandenginste, B.G.M., Buydens, L.M.C., De Jong, S., Lewi, P.J.,
- Smeyers-Verbeke, J. (1997) Handbook of Chemometrics and Qualimetrics: Part A,
- p. 200
-}
-\examples{
-# This is example 7 from Chapter 8 in Massart et al. (1997)
-data(massart97ex1)
-m <- lm(y ~ x, data = massart97ex1)
-inverse.predict(m, 15) # 6.1 +- 4.9
-inverse.predict(m, 90) # 43.9 +- 4.9
-inverse.predict(m, rep(90,5)) # 43.9 +- 3.2
-}
-\keyword{manip}
diff --git a/man/ipowfunc.Rd b/man/ipowfunc.Rd
deleted file mode 100644
index e09e590..0000000
--- a/man/ipowfunc.Rd
+++ /dev/null
@@ -1,33 +0,0 @@
-\name{ipowfunc}
-\alias{ipowfunc}
-\title{Power function}
-\description{
- Inverse of the arithmetic power function \code{\link{powfunc}} used for
- modelling univariate nonlinear calibration data. }
-\usage{
- ipowfunc(x,a,b)
-}
-\arguments{
- \item{x}{
- Independent variable}
- \item{a}{
- Coefficient}
- \item{b}{
- Exponent}
-}
-\value{
- The result of evaluating the function
- \deqn{f(x) = \frac{y}{a}^\frac{1}{b}}{f(x) = y/a^1/b}
- which is the inverse of the function defined by \code{\link{powfunc}}
-}
-\author{
- Johannes Ranke
- \email{jranke@uni-bremen.de}
- \url{http://www.uft.uni-bremen.de/chemie/ranke}
-}
-\seealso{
- The original function \code{\link{powfunc}}.
-}
-\keyword{models}
-\keyword{regression}
-\keyword{nonlinear}
diff --git a/man/lod.Rd b/man/lod.Rd
deleted file mode 100644
index e468e1d..0000000
--- a/man/lod.Rd
+++ /dev/null
@@ -1,83 +0,0 @@
-\name{lod}
-\alias{lod}
-\alias{lod.lm}
-\alias{lod.rlm}
-\alias{lod.default}
-\title{Estimate a limit of detection (LOD)}
-\usage{
- lod(object, \dots, alpha = 0.05, beta = 0.05, method = "default")
-}
-\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},
- optionally from a weighted regression.
- }
- \item{\dots}{
- Placeholder for further arguments that might be needed by
- future implementations.
- }
- \item{alpha}{
- The error tolerance for the decision limit (critical value).
- }
- \item{beta}{
- The error tolerance beta for the detection limit.
- }
- \item{method}{
- The default method uses a prediction interval at the LOD
- for the estimation of the LOD, which obviously requires
- iteration. This is described for example in Massart, p. 432 ff.
- The \dQuote{din} method uses the prediction interval at
- x = 0 as an approximation.
- }
-}
-\value{
- A list containig the corresponding x and y values of the estimated limit of
- detection of a model used for calibration.
-}
-\description{
- The decision limit (German: Nachweisgrenze) is defined as the signal or
- analyte concentration that is significantly different from the blank signal
- with a first order error alpha (one-sided significance test).
- The detection limit, or more precise, the minimum detectable value
- (German: Erfassungsgrenze), is then defined as the signal or analyte
- concentration where the probability that the signal is not detected although
- the analyte is present (type II or false negative error), is beta (also a
- one-sided significance test).
-}
-\note{
- - The default values for alpha and beta are the ones recommended by IUPAC.
- - The estimation of the LOD in terms of the analyte amount/concentration
- xD from the LOD in the signal domain SD is done by simply inverting the
- calibration function (i.e. assuming a known calibration function).
- - The calculation of a LOD from weighted calibration models requires
- a weights argument for the internally used \code{\link{predict.lm}}
- function, which is currently not supported in R.
-}
-\references{
- Massart, L.M, Vandenginste, B.G.M., Buydens, L.M.C., De Jong, S., Lewi, P.J.,
- Smeyers-Verbeke, J. (1997) Handbook of Chemometrics and Qualimetrics: Part A,
- Chapter 13.7.8
-
- J. Inczedy, T. Lengyel, and A.M. Ure (2002) International Union of Pure and
- Applied Chemistry Compendium of Analytical Nomenclature: Definitive Rules.
- Web edition.
-
- Currie, L. A. (1997) Nomenclature in evaluation of analytical methods including
- detection and quantification capabilities (IUPAC Recommendations 1995).
- Analytica Chimica Acta 391, 105 - 126.
-}
-\examples{
-data(din32645)
-m <- lm(y ~ x, data = din32645)
-lod(m)
-
-# The critical value (decision limit, German Nachweisgrenze) can be obtained
-# by using beta = 0.5:
-lod(m, alpha = 0.01, beta = 0.5)
-}
-\seealso{
- Examples for \code{\link{din32645}}
-}
-\keyword{manip}
diff --git a/man/loq.Rd b/man/loq.Rd
deleted file mode 100644
index 7541e77..0000000
--- a/man/loq.Rd
+++ /dev/null
@@ -1,77 +0,0 @@
-\name{loq}
-\alias{loq}
-\alias{loq.lm}
-\alias{loq.rlm}
-\alias{loq.default}
-\title{Estimate a limit of quantification (LOQ)}
-\usage{
- loq(object, \dots, alpha = 0.05, k = 3, n = 1, w.loq = "auto",
- var.loq = "auto")
-}
-\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},
- optionally from a weighted regression. If weights are specified
- in the model, either \code{w.loq} or \code{var.loq} have to
- be specified.
- }
- \item{alpha}{
- The error tolerance for the prediction of x values in the calculation.
- }
- \item{\dots}{
- Placeholder for further arguments that might be needed by
- future implementations.
- }
- \item{k}{
- The inverse of the maximum relative error tolerated at the
- desired LOQ.
- }
- \item{n}{
- The number of replicate measurements for which the LOQ should be
- specified.
- }
- \item{w.loq}{
- The weight that should be attributed to the LOQ. Defaults
- to one for unweighted regression, and to the mean of the weights
- for weighted regression. See \code{\link{massart97ex3}} for
- an example how to take advantage of knowledge about the
- variance function.
- }
- \item{var.loq}{
- The approximate variance at the LOQ. The default value is
- calculated from the model.
- }
-}
-\value{
- The estimated limit of quantification for a model used for calibration.
-}
-\description{
- The limit of quantification is the x value, where the relative error
- of the quantification given the calibration model reaches a prespecified
- value 1/k. Thus, it is the solution of the equation
- \deqn{L = k c(L)}{L = k * c(L)}
- where c(L) is half of the length of the confidence interval at the limit L
- (DIN 32645, equivalent to ISO 11843). c(L) is internally estimated by
- \code{\link{inverse.predict}}, and L is obtained by iteration.
-}
-\note{
- - IUPAC recommends to base the LOQ on the standard deviation of the signal
- where x = 0.
- - The calculation of a LOQ based on weighted regression is non-standard
- and therefore not tested. Feedback is welcome.
-}
-\examples{
-data(massart97ex3)
-attach(massart97ex3)
-m <- lm(y ~ x)
-loq(m)
-
-# We can get better by using replicate measurements
-loq(m, n = 3)
-}
-\seealso{
- Examples for \code{\link{din32645}}
-}
-\keyword{manip}
diff --git a/man/massart97ex1.Rd b/man/massart97ex1.Rd
deleted file mode 100644
index 44e1b85..0000000
--- a/man/massart97ex1.Rd
+++ /dev/null
@@ -1,17 +0,0 @@
-\name{massart97ex1}
-\docType{data}
-\alias{massart97ex1}
-\title{Calibration data from Massart et al. (1997), example 1}
-\description{
- Sample dataset from p. 175 to test the package.
-}
-\usage{data(massart97ex1)}
-\format{
- A dataframe containing 6 observations of x and y data.
-}
-\source{
- Massart, L.M, Vandenginste, B.G.M., Buydens, L.M.C., De Jong, S., Lewi, P.J.,
- Smeyers-Verbeke, J. (1997) Handbook of Chemometrics and Qualimetrics: Part A,
- Chapter 8.
-}
-\keyword{datasets}
diff --git a/man/massart97ex3.Rd b/man/massart97ex3.Rd
deleted file mode 100644
index efdcf02..0000000
--- a/man/massart97ex3.Rd
+++ /dev/null
@@ -1,51 +0,0 @@
-\name{massart97ex3}
-\docType{data}
-\alias{massart97ex3}
-\title{Calibration data from Massart et al. (1997), example 3}
-\description{
- Sample dataset from p. 188 to test the package.
-}
-\usage{data(massart97ex3)}
-\format{
- A dataframe containing 6 levels of x values with 5
- observations of y for each level.
-}
-\examples{
-data(massart97ex3)
-attach(massart97ex3)
-yx <- split(y, x)
-ybar <- sapply(yx, mean)
-s <- round(sapply(yx, sd), digits = 2)
-w <- round(1 / (s^2), digits = 3)
-weights <- w[factor(x)]
-m <- lm(y ~ x, w = weights)
-calplot(m)
-
-# The following concords with the book p. 200
-inverse.predict(m, 15, ws = 1.67) # 5.9 +- 2.5
-inverse.predict(m, 90, ws = 0.145) # 44.1 +- 7.9
-
-# The LOD is only calculated for models from unweighted regression
-# with this version of chemCal
-m0 <- lm(y ~ x)
-lod(m0)
-
-# Limit of quantification from unweighted regression
-loq(m0)
-
-# For calculating the limit of quantification from a model from weighted
-# regression, we need to supply weights, internally used for inverse.predict
-# If we are not using a variance function, we can use the weight from
-# the above example as a first approximation (x = 15 is close to our
-# loq approx 14 from above).
-loq(m, w.loq = 1.67)
-# The weight for the loq should therefore be derived at x = 7.3 instead
-# of 15, but the graphical procedure of Massart (p. 201) to derive the
-# variances on which the weights are based is quite inaccurate anyway.
-}
-\source{
- Massart, L.M, Vandenginste, B.G.M., Buydens, L.M.C., De Jong, S., Lewi, P.J.,
- Smeyers-Verbeke, J. (1997) Handbook of Chemometrics and Qualimetrics: Part A,
- Chapter 8.
-}
-\keyword{datasets}
diff --git a/man/powfunc.Rd b/man/powfunc.Rd
deleted file mode 100644
index 73fe3b0..0000000
--- a/man/powfunc.Rd
+++ /dev/null
@@ -1,32 +0,0 @@
-\name{powfunc}
-\alias{powfunc}
-\title{Power function}
-\description{
- Arithmetic power function for modelling univariate nonlinear calibration data.
-}
-\usage{
- powfunc(x,a,b)
-}
-\arguments{
- \item{x}{
- Independent variable}
- \item{a}{
- Coefficient}
- \item{b}{
- Exponent}
-}
-\value{
- The result of evaluating the function
- \deqn{f(x) = a x^b}{f(x) = a * x^b}
-}
-\author{
- Johannes Ranke
- \email{jranke@uni-bremen.de}
- \url{http://www.uft.uni-bremen.de/chemie/ranke}
-}
-\seealso{
- The inverse of this function \code{\link{ipowfunc}}.
-}
-\keyword{models}
-\keyword{regression}
-\keyword{nonlinear}

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