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trees {datasets}

Girth, Height and Volume for Black Cherry Trees
Package: 
datasets
Version: 
R 3.0.2

Description

This data set provides measurements of the girth, height and volume of timber in 31 felled black cherry trees. Note that girth is the diameter of the tree (in inches) measured at 4 ft 6 in above the ground.

Usage

trees

References

Atkinson, A. C. (1985) Plots, Transformations and Regression. Oxford University Press.

Examples

require(stats); require(graphics)
pairs(trees, panel = panel.smooth, main = "trees data")
plot(Volume ~ Girth, data = trees, log = "xy")
coplot(log(Volume) ~ log(Girth) | Height, data = trees,
       panel = panel.smooth)
summary(fm1 <- lm(log(Volume) ~ log(Girth), data = trees))
summary(fm2 <- update(fm1, ~ . + log(Height), data = trees))
step(fm2)
## i.e., Volume ~= c * Height * Girth^2  seems reasonable

Documentation reproduced from R 3.0.2. License: GPL-2.