On this Picostat.com statistics page, you will find information about the ToothGrowth data set which pertains to The Effect of Vitamin C on Tooth Growth in Guinea Pigs. The ToothGrowth data set is found in the datasets R package. You can load the ToothGrowth data set in R by issuing the following command at the console data("ToothGrowth"). This will load the data into a variable called ToothGrowth. If R says the ToothGrowth 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 ToothGrowth R data set. The size of this file is about 760 bytes.
The Effect of Vitamin C on Tooth Growth in Guinea Pigs
The response is the length of odontoblasts (cells responsible for
tooth growth) in 60 guinea pigs. Each animal received one of three
dose levels of vitamin C (0.5, 1, and 2 mg/day) by one of two delivery
methods, (orange juice or ascorbic acid (a form of vitamin C and coded
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/day
C. I. Bliss (1952)
The Statistics of Bioassay.
McNeil, D. R. (1977)
Interactive Data Analysis.
New York: Wiley.
Crampton, E. W. (1947)
The growth of the odontoblast of the incisor teeth as a criterion of
vitamin C intake of the guinea pig. The Journal of Nutrition
coplot(len ~ dose | supp, data = ToothGrowth, panel = panel.smooth,
xlab = "ToothGrowth data: length vs dose, given type of supplement")
Dataset imported from https://www.r-project.org.