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 !r sire units

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

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?

Andrew Swan
CSIRO Division of Animal Production
Pastoral Research Laboratory
Armidale  2350  AUSTRALIA
ph.  +61 (0)2 67761377
fax  +61 (0)2 67761333