Re: Two questions

From: Arthur <asremlforum_at_VSNI.CO.UK>
Date: Sun, 5 Jul 2009 23:28:46 +0100

Dear Joseph,
This seems to be the third query of this type in a week, unless I'm confused and have double up.

Firstfor the basic repeatability model (animal model)

        I wrote in reply to the first:
        If you have one trait, the basic model would be
         milk ~ mu ... !r animal ide(animal)
        [Assuming you have a pedigree on animal, else omit the ide(animal)
        The bivariate version of this is
         milk fat ~ Trait ... !r Trait.animal Trait.ide(animal)
        1 2 2
        Trait 0 US !GP
        Trait.animal 2
        Trait0 US !GP
        animal 0 AINV
        Trait.ide(animal) 2
        Trait0 US !GP

"I also have birth weight and weight of first week from full sib chickens. What is the proper program for predicting maternal genetic and common environmental effects in univariate and bivariate analysis? "

Again, assuming an animal model,
and with pedigree information/relationships on the dams

!RENAME !ARG 1 2 12
Maternal Model
 Chick !P
 Sire !P
 Dam !P
chicken.ped !skip 1 !ALPHA
chicken.csv !skip

!PART 1 # Univariate maternal model

 bwt ~ mu !r Chick Dam ide(Dam)

!PART 2 # Univariate maternal model

 wt1 ~ mu !r Chick Dam ide(Dam)

!PART 12 # Bivariate maternal model

 bwt wt1 ~ Trait !r Trait.Chick Trait.Dam Trait.ide(Dam)
1 2 3
Trait 0 US !GP

Trait.Chick 2
Trait 0 US !GP
Chick 0 AINV

Trait.Dam 2
Trait 0 US !GP
Dam 0 AINV

Trait.ide(Dam) 2
Trait 0 US !GP

However, this final model will not converge if the former univariate models
do not report positive components for all four variance components.

Furthermore, since bet and wt1 are expected to be highly correlated,
there is a high chance that the estimated covariances will be on the boundary, also casusing convergence problems.

Arthur Gilmour

Retired Principal Research Scientist (Biometrics)

-------------------- m2f --------------------

Sent using Mail2Forum (

Read this topic online here:

-------------------- m2f --------------------
Received on Mon Jul 05 2009 - 23:28:46 EST

This webpage is part of the ASReml-l discussion list archives 2004-2010. More information on ASReml can be found at the VSN website. This discussion list is now deprecated - please use the VSN forum for discussion on ASReml. (These online archives were generated using the hypermail package.)