Repeated measures example

Wolfinger rat data

Wolfinger (1996) summarises a range of variance structures that can be fitted to repeated measures data and demonstrates the models using five weights taken weekly on 27 rats subjected to 3 treatments.

This command file demonstrates a multivariate analysis of the five repeated measures. Note that the two dimensional structure for common error meets the requirement of independent units and is correctly ordered traits with units.

 Wolfinger rat data
  treat !A
  wt0 wt1 wt2 wt3 wt4
 rat.dat
 wt0 wt1 wt2 wt3 wt4 ~ Trait*treat
 residual units.us(Trait)

To fit other residual variance structures, !ASUV is required. For example

 Wolfinger rat data
  treat !A
  wt0 wt1 wt2 wt3 wt4
 rat.dat      !ASUV
 wt0 wt1 wt2 wt3 wt4 ~ Trait*treat
 residual units.ar1h(Trait)

Return to index