ToothGrowth             package:datasets             R Documentation

The Effect of Vitamin C on Tooth Growth in Guinea Pigs

Description:

     The response is the length of odontoblasts (teeth) in each of 10
     guinea pigs at each of three dose levels of Vitamin C (0.5, 1, and
     2 mg) with each of two delivery methods (orange juice or ascorbic
     acid).

Usage:

     ToothGrowth

Format:

     A data frame with 60 observations on 3 variables.

       [,1]  len   numeric  Tooth length
       [,2]  supp  factor   Supplement type (VC or OJ).
       [,3]  dose  numeric  Dose in milligrams.

Source:

     C. I. Bliss (1952) _The Statistics of Bioassay_. Academic Press.

References:

     McNeil, D. R. (1977) _Interactive Data Analysis_. New York: Wiley.

Examples:

     require(graphics)
     coplot(len ~ dose | supp, data = ToothGrowth, panel = panel.smooth,
            xlab = "ToothGrowth data: length vs dose, given type of supplement")

