Thanks, I'll look at that.
In the meantime, the code below is what I came up with myself. It does
what I want
# SelectCases(dat,crit) == subset(dat, crit, drop=FALSE)
SENSICK.AvScores<- function( dat=SENSICK.items.tr )
{
n<-nlevels(dat$Symptom)
data.frame(
Patient
René J.V. Bertin gmail.com> writes:
> I have some data in a data.frame where for each of a number of
> subjects, I have scores for all of a number of symptoms.
>
> Subjects are subdivided in a number of groups, which have unequal sizes.
>
> I'd like to plot between-group differences in the scor
Hello,
I have some data in a data.frame where for each of a number of
subjects, I have scores for all of a number of symptoms.
Subjects are subdivided in a number of groups, which have unequal sizes.
I'd like to plot between-group differences in the scores on the
various symptoms. Ideally, that
