Re: [R] Treatment-response analysis along time

From: Dimitris Rizopoulos <>
Date: Wed 10 Aug 2005 - 17:21:25 EST

you haven't told us what kind of variable you measure, but either way look at lmer() function in lme4 package which fits both linear and generalized linear mixed-effects models.

I hope it helps.


Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium

Tel: +32/16/336899
Fax: +32/16/337015

Dear R people,
I wonder if you could give me a hand with some of my data. I have a very
typical analysis in biology, however it is difficult for me to find the
right way to analyse. I had a group of animals, I gave them a treatment, and
I measure a variable along time -one´s per day- along 5 days,for example(fake data):
Animals Time1 Time2 Time3 Time4

1            1         5        3        1
2            2         7        4        1
3            5         5        3        1
4            1         3        7        2
5            2         7        7        1
Please, notice that all the animals get the same treatment, and there are no
  control -animals which has no received any treatment. Normally I handle this kind of data with SPSS and Repeated Measurement
analysis. That tell me if there is a change along the time, but no information about when the treatment start to be effective, when the effect
has pass. Besides, i would like to be able to handle this data with R. I have been looking at Crawley's S-plus book, and I cannot find similar
example as I have, not either in the Dalgaard´s introduction to R, because
he uses an example where different animals are measured as each time -using
time as a factor in a one way anova (I am hope I am right). Thanks for your help and time.
Best regards
Felix mailing list PLEASE do read the posting guide! mailing list PLEASE do read the posting guide! Received on Wed Aug 10 17:27:46 2005

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