Re: multivariate genetic analysis using SPLUS asreml

From: <arthur.gilmour_at_DPI.NSW.GOV.AU>
Date: Thu, 18 Oct 2007 11:31:47 +1000

Dear Derek,

I understand your main issue wanting to calculate the genetic correlation
and its standard error.

As we noted separately, ASReml-S does not appear to have the equivalent of
ASRemls .vvp
file. However, in the case of a multivariate model, the approximate
variance for the
variance parameters is just the inverse of the AI matrix which you do

You seem to be saying though that you havn't properly sorted the function
to calculate the SE
of the derived correlation.

One work around is to parameterise the variance model so that the
correalation is directly
estimated. Then, its SE will be easily derived from the Z-ratio

I'm expert in ASReml rather than ASReml-S, but it should just be a matter
 replacing us(trait) with corgh(trait).

The model is equivalent, so you should be able to see the connection.

On the other issues, I support Brian's comments.

May Jesus Christ be gracious to you,

Arthur Gilmour, His servant .

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Received on Mon Oct 18 2007 - 11:31:47 EST

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