rats R Documentation

## Rats Diet Experiment

### Description

“Weil (1970) in Table 1 gives the results from an experiment comprising two treatments. One group of 16 pregnant female rats was fed a control diet during pregnancy and lactation, the diet of a second group of 16 pregnant females was treated with a chemical. For each litter the number n of pups alive at 4 days and the number x of pups that survived the 21 day lactation period were recorded.” (Williams, 1975, p. 951).

### Usage

data(rats)

### Format

A data frame with 32 observations on the following 3 variables.

group

A factor with levels CTRL and TREAT

n

A numeric vector: the number of pups alive at 4 days.

y

A numeric vector: the number of pups that survived the 21 day lactation.

### Source

Williams, D.A., 1975. The analysis of binary responses from toxicological experiments involving reproduction and teratogenicity. Biometrics 31, 949-952.

### References

Weil, C.S., 1970. Selection of the valid number of sampling units and a consideration of their combination in toxicological studies involving reproduction, teratogenesis or carcinogenesis. Fd. Cosmet. Toxicol. 8, 177-182.