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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} |