treevol {datana}

Diameter, height and volume for Black Cherry Trees

Description

This data set provides measurements of the diameter, height and volume of timber in 31 felled black cherry trees. It is a slight modification of the dataframe 'trees' of the 'datasets' R package.

Usage

data(treevol)

Format

A data frame with 31 observations and three variables

dbh

Diameter at breast height, in cm

htot

Total height, in m

volume

Volume of timber, in m^{3}

Source

Ryan, T. A., Joiner, B. L. and Ryan, B. F. (1976) The Minitab Student Handbook. Duxbury Press.

Examples

pairs(treevol, panel = panel.smooth, main = "treevol data frame")
plot(volume ~ dbh, data = treevol, log = "xy")
coplot(log(volume) ~ log(dbh) | htot, data = treevol,
       panel = panel.smooth)
summary(m1 <- lm(log(volume) ~ log(dbh), data = treevol))
summary(m2 <- update(m1, ~ . + log(htot), data = treevol))
anova(m1,m2)