On this Picostat.com statistics page, you will find information about the trees data set which pertains to Girth, Height and Volume for Black Cherry Trees. The trees data set is found in the datasets R package. You can load the trees data set in R by issuing the following command at the console data("trees"). This will load the data into a variable called trees. If R says the trees data set is not found, you can try installing the package by issuing this command install.packages("datasets") and then attempt to reload the data. If you need to download R, you can go to the R project website. You can download a CSV (comma separated values) version of the trees R data set. The size of this file is about 406 bytes.
Girth, Height and Volume for Black Cherry Trees
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
A data frame with 31 observations on 3 variables.
|| Tree diameter in inches
|| Height in ft
|| Volume of timber in cubic ft
Ryan, T. A., Joiner, B. L. and Ryan, B. F. (1976)
The Minitab Student Handbook.
Atkinson, A. C. (1985)
Plots, Transformations and Regression.
Oxford University Press.
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))
## i.e., Volume ~= c * Height * Girth^2 seems reasonable
Dataset imported from https://www.r-project.org.