Re: repeated measures models
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Re: repeated measures models

Arthur wrote:-

>Lets start with 
>  intake1 intake2 intake3 other ~ Trait Tr.line Tr.feedflock Tr.damage,
>  Tr.brtype !r Tr.sire
> 1 2 0 
> 1728   #no. of animals in the data
> Tr 0 US  E11 E12 E22 E31 E32 E33 E41 E42 E43 E44  !=1212213330
> Tr.sire 2
> Tr 0 US  G11 G12 G22 G31 G32 G33 G41 G42 G43 G44  !=4545546660
> sire
>SO what we have here is setting the model up as standard multivariate
>and then constraining the intake variances and covariances.
>You could of course fit it with unconstrained variances.
>The way the first model was fitted, the 'units' term gave the E12 E32 R32
>covariances and the  'units + residual' gave the E11, E22 and E33 terms.
>The sire term gave G11=G21=G22=G31=G32=G33
>When you get this running, you may see how to extend to more complex models.

Okay, I can see how that might work.

But for a repeatability model, you need to have the
genetic correlation equal to one among the 3 intake
traits. I don't see how you do this, I know it
uses the and() function in some way, but I don't understand it.