 missing data for either the responses or the covariates. The
question of interest is to assess whether the treatment is effective
and to estimate its effect.
</p>
<p>Note that the data are in long form, i.e, repeated measurments are
stored as additional rows in the data frame.
</p>


<h3>Source</h3>

<p>C. S. Davis (1991), Semi-parametric and non-parametric methods
for the analysis of repeated measurements with applications to
clinical trials. <em>Statistics in Medicine</em>, <b>10</b>, 
1959&ndash;1980.
<