mice {SMPracticals}

Mice Deaths from Radiation

Description

RFM male mice were exposed to 300 rads of x-radiation at 5–6 weeks of age. The causes of death were thymic lymphoma, reticulum cell sarcoma, and other. Some of the mice were kept in a conventional environment, and the others in a germ-free environment.

Usage

data(mice)

Format

A data frame with 177 observations on the following 4 variables.

type

Environment type (factor)

cause

Cause of death

status

Censoring indicator, with 1 indicating death

y

Age at death (weeks)

Source

Hoel, D. G. and Walburg, H. E. (1972) Statistical analysis of survival experiments. Journal of the National Cancer Institute, 49, 361–372.

References

Davison, A. C. (2003) Statistical Models. Cambridge University Press. Page 200.

Examples

data(mice)
library(survival)
fit <- survfit(Surv(y,status)~cause,data=mice[1:95,]) # first group
plot(fit,lty=c(3,2,1))