robustbase: SiegelsEx – R documentation

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SiegelsEx

Siegel's Exact Fit Example Data

Description

A small counterexample data set devised by Andrew Siegel. Six (out of nine) data points lie on the line y = 0 such that some robust regression estimators exhibit the “exact fit” property.

Usage

data(SiegelsEx, package="robustbase")

Format

A data frame with 9 observations on the following 2 variables.

x: a numeric vector
y: a numeric vector

Source

Emerson and Hoaglin (1983, p.139)

References

Peter J. Rousseeuw and Annick M. Leroy (1987) Robust Regression and Outlier Detection Wiley, p.60–61

Examples

data(SiegelsEx)
plot(SiegelsEx, main = "Siegel's example for 'exact fit'")
abline(          lm(y ~ x, data = SiegelsEx))
abline(MASS::lqs(y ~ x, data = SiegelsEx, method = "lms"), col = 2)
legend("topright", leg = c("lm", "LMS"), col=1:2, lwd=1, inset = 1/20)

robustbase

Basic Robust Statistics

v0.93-7

GPL (>= 2)

Authors

Martin Maechler [aut, cre] (<https://orcid.org/0000-0002-8685-9910>), Peter Rousseeuw [ctb] (Qn and Sn), Christophe Croux [ctb] (Qn and Sn), Valentin Todorov [aut] (most robust Cov), Andreas Ruckstuhl [aut] (nlrob, anova, glmrob), Matias Salibian-Barrera [aut] (lmrob orig.), Tobias Verbeke [ctb, fnd] (mc, adjbox), Manuel Koller [aut] (mc, lmrob, psi-func.), Eduardo L. T. Conceicao [aut] (MM-, tau-, CM-, and MTL- nlrob), Maria Anna di Palma [ctb] (initial version of Comedian)

Initial release

2021-01-04