egde {CorrBin}

EGDE data

Description

The data set is based on a developmental toxicity experiment on the effect of ethylene glycol diethyl ether (EGDE) on fetal development of New Zealand white rabbits. In the study, four groups of pregnant does were randomly assigned to dose levels $0, 25, 50$, and $100$ milligrams per kilogram body weight of EGDE. For each litter and at each dose level, the adverse response used is the combined number of fetal malformation and fetal death.

Usage

data(egde)

Format

A 'CBData' object, that is a data frame with the following variables

Trt	factor giving treatment group
ClusterSize	the size of the litter
NResp	the number of affected fetuses
Freq	the number of litters with the given ClusterSize/NResp combination

Source

Krewski, D., Zhu, Y., and Fung, K. (1995). Statistical analysis of overdispersed multinomial data from developmental toxicity studies. In Statistics in Toxicology, Ed. B. Morgan, pp.\ 151–179. New York: Oxford University Press.

Examples

  data(egde)
  stripchart(I(NResp/ClusterSize)~Trt, cex=sqrt(egde$Freq), data=egde, pch=1, 
             method="jitter", vertical=TRUE, ylab="Proportion affected")