Specifying variance components
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Specifying variance components

I need some help with specifying variance components under a multivariate 
model with maternal effects.  The data set does not have sufficient 
information to estimate the additive-maternal covariance.  So I am just 
fitting dam as a second effect.

Below is a my current .as file (simplified as the random effects are the 
important part at present), is this a correct specification?
Is this the same as saying:
wt0 wtw ~ Trait !r Tr.tag at(Tr,1).dam at(Tr,2).dam ?

If I decide to fit only a maternal effect to wt0, the model changes to:
wt0 wtw ~ Trait !r Tr.tag at(Tr,1).dam

How would I specify starting variance components for the dam component?

Thanks in advance for any comments,
Bruce Southey

Bivariate with maternal
 tag  !p  # 2525 animals in pedigree
 dam  !p
 br 6 !I
 yb 6 !I
 sx   2 !I
 aod   4 !I
 bd    !-12260
wt.dat  !MAXIT 1 # !CONTINUE
wt0 wtw ~ Trait !r Tr.tag Tr.dam
1 2 2   # !step 0.0001
0 0 0
Trait 0 US 0.29202 0.63988 3.0156
Tr.tag 2
Trait 0 US 0.28609 0.85243 4.6901
tag 0 0
Tr.dam 2
2 0 DIAG 0.2  4.2
dam 0 0

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