Dear all,

I have been using the contrast library in my teaching for the last couple 
of years and am right in the middle of this year's round. In the last week 
R has been updated to version 2.14.0 on our computers. This has had the 
unfortunate effect of meaning the contrasts library no longer works, as 
the Design library is no longer available. I wonder if anyone has a fix 
for this...or alternatively can tell me another package that is as simple 
to use (the students won't cope with anything more complicated - we're all 
biologists not statisticians).

I hope someone can help.

Here is a typical bit of code I'm currently running so you can see what 
I'm trying to do:

exptime is a covariate and both infstat and status are factors

mod<-glm(propalive~exptime+infstat+status+ 
        infstat:status,
        data=dat)

library(contrast)

contrast(mod3,
   a = list(status = levels(dat$status), infstat="control", exptime=8230),
   b = list(status = levels(dat$status), infstat="infected",exptime=8230))

any help gratefully received,

Jo

Dr Joanne Lello
Cardiff University
School of Biosciences
Organism and Environment Group
Biomedical Sciences Building
Museum Avenue
Cardiff
CF10 3AX
Tel: 02920 875885
E-mail: lelloj@cardiff.ac.uk
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