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wood

Modified Data on Wood Specific Gravity


Description

The original data are from Draper and Smith (1966) and were used to determine the influence of anatomical factors on wood specific gravity, with five explanatory variables and an intercept. These data were contaminated by replacing a few observations with outliers.

Usage

data(wood, package="robustbase")

Format

A data frame with 20 observations on the following 6 variables.

x1, x2, x3, x4, x5

explanatory “anatomical” wood variables.

y

wood specific gravity, the target variable.

Source

Draper and Smith (1966, p.227)

Peter J. Rousseeuw and Annick M. Leroy (1987) Robust Regression and Outlier Detection Wiley, p.243, table 8.

Examples

data(wood)
plot(wood)
summary( lm.wood <-        lm(y ~ ., data = wood))
summary(rlm.wood <- MASS::rlm(y ~ ., data = wood))
summary(lts.wood <-    ltsReg(y ~ ., data = wood))

wood.x <- as.matrix(wood)[,1:5]
c_wood <- covMcd(wood.x)
c_wood

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

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