ToothGrowth {datasets} | R Documentation

## The Effect of Vitamin C on Tooth Growth in Guinea Pigs

### Description

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 as `VC`).

### 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/day

### Source

C. I. Bliss (1952) The Statistics of Bioassay. Academic Press.

### References

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 33(5): 491–504. http://jn.nutrition.org/content/33/5/491.full.pdf

### Examples

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

[Package datasets version 3.3.2 Index]