poisons {SMPracticals}

Survival Times for Poisoned Animals

Description

In an experiment to assess the usefulness of treatments for poisons, 48 animals were split randomly into 12 groups of 4. Each group was administered one of three poisons, and one of four treatments, giving a 3x4 factorial design with 4 replicates.

Usage

data(poisons)

Format

A data frame with 48 observations on the following 3 variables.

time

Survival time (units of 10 hours)

poison

Factor giving poison

treat

Factor giving treatment

Source

Box, G. E. P. and Cox, D. R. (1964) An analysis of transformations (with Discussion). Journal of the Royal Statistical Society series B, 26, 211–246.

References

Davison, A. C. (2003) Statistical Models. Cambridge University Press. Page 391.

Examples

data(poisons)
fit <- lm(time~poison+treat,data=poisons)
library(MASS)
boxcox(time~poison+treat,data=poisons)