PlantGrowth | R Documentation |
Results from an Experiment on Plant Growth
Description
Results from an experiment to compare yields (as measured by dried weight of plants) obtained under a control and two different treatment conditions.
Usage
PlantGrowth
Format
A data frame of 30 cases on 2 variables.
[, 1] | weight | numeric |
[, 2] | group | factor |
The levels of group
are ‘ctrl’, ‘trt1’,
and ‘trt2’.
Source
Dobson, A. J. (1983) An Introduction to Statistical Modelling. London: Chapman and Hall.
Examples
## One factor ANOVA example from Dobson's book, cf. Table 7.4:
require(stats); require(graphics)
boxplot(weight ~ group, data = PlantGrowth, main = "PlantGrowth data",
ylab = "Dried weight of plants", col = "lightgray",
notch = TRUE, varwidth = TRUE)
anova(lm(weight ~ group, data = PlantGrowth))