

   PlantGrowth {base}                           R Documentation

   RReessuullttss ffrroomm aann EExxppeerriimmeenntt oonn PPllaanntt GGrroowwtthh

   DDeessccrriippttiioonn::

        Results from an experiment to compare yields (as mea-
        sured by dried weight of plants) obtained under a con-
        trol and two different treatment conditions.

   UUssaaggee::

        data(PlantGrowth)

   FFoorrmmaatt::

        A data frame of 30 cases on 2 variables.

         [, 1]     weight     numeric
         [, 2]     group      factor

        The levels of `group' are `ctrl', `trt1', and `trt2'.

   SSoouurrccee::

        Dobson, A. J. (1983).  An Introduction to Statistical
        Modelling.  London: Chapman and Hall.

   EExxaammpplleess::

        ## One factor ANOVA example from Dobson's book, cf. Table 7.4:
        data(PlantGrowth)
        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))

