repeated measures models
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repeated measures models



hi, i'm having trouble working out how to fit repeated measures models
in asreml. i have a data file with one record per "animal", with 3
observations of the same trait, which looks something like this:

tag intake1 intake2 intake3 ... (other fields).
1     x1      y1      z1    ...
2     x2      NA      z2    ...

(i have missing values for some animals)

i fit a model like this

intake1 intake2 intake3 ~ Trait Tr.line Tr.feedflock Tr.damage,
 Tr.brtype Tr.sex !r sire units

1 2 0 !ASUV
1728   #no. of animals in the data
Tr

this seems to work ok: i get variance estimates which look sensible.

my next step is to add a second trait, which doesn't have repeated
observations. i can't for the life of me think how to specify this
model. what i would like to do is estimate "sire" and "residual"
covariance matrices for "intake" and my second trait, and a permanent
environment variance for "intake" (the "units" component from the above
analysis). can anyone help me here?

thanks
-- 
Andrew Swan
CSIRO Division of Animal Production
Pastoral Research Laboratory
Armidale  2350  AUSTRALIA
ph.  +61 (0)2 67761377
fax  +61 (0)2 67761333
email: andrew@chiswick.anprod.csiro.au