rat.growth {SMPracticals}

Rat Growth Data

Description

Data on the weights of 30 rats each week for 5 weeks.

Usage

data(rat.growth)

Format

A data frame with 150 observations on the following 3 variables.

rat

a factor with levels 1-30

week

takes values 0-4

y

rat weight (units unspecified)

Source

Gelfand, A. E., Hills, S. E., Racine-Poon, A. and Smith, A. F. M. (1990) Illustration of Bayesian inference in normal data models using Gibbs sampling. Journal of the American Statistical Association, 85, 972–985.

References

Davison, A. C. (2003) Statistical Models. Cambridge University Press. Page 460.

Examples

data(rat.growth)
library(nlme)
rat.fit <- groupedData( y~poly(week,2) | rat,
                   data = rat.growth,
                   labels = list( x = "Week",
                     y = "Weight" ),
                   units = list( x = "", y = "(?)") )

summary(lme(rat.fit))