Re: Repeated measures
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Re: Repeated measures

> Hi,
> Working with asreml using polynomial random regressions I have the same
> problem than Dave Johnson: 0 covariance between the polynomial
> coefficients. If I specify a US matrix with 0 covariances or a DIAG
> matrix the program works, but trying to specify covariances different
> from 0 leads to non-convergence.  Does anyone know why this happen?

Are you using the pol() function.  If so, the covariance between
intercept and slope is expected to be quite low.  
Starting US with zero covariance does not fix the covariance at zero
so it should converge.  Otherwise, start with a very small covariance.

Look at what happens with the lack of convergence - typically components
see-saw erratically.  Starting values have a big influence.
Using !STEP .001  may also help.

You could look in the .res file [after using DIAG] and see there the empirical
between the intercepts and slopes.  This might help also.

> Another related question: If I use just a DIAG structure and then check
> the .sln file there is a problem with the identities of the solutions.
> Each identity looks like a series of black squares followed by .001,
> .002, etc. So, I know what solution corresponds to each term of the
> polynomial, but I can't know to what individual.

I thought I had sorted out labelling bugs.  You may get proper labels
if you convert  animal.pol() to pol().animal.
Maybe there isn't enough space in the output field for the label.
As a work-around, 
assuming you are talking of individuals from the pedigree, 
take the identies from a simpoler model (fit animal rather than the animal 
interaction): theidentities will be in the same order
> If it is of any help, I'm using asreml version April 16 1998 for win95.
> Thanks a lot,
> Luis
> &~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Luis Apiolaza
> Institute of Veterinary, Animal and Biomedical Sciences
> Massey University
> Palmerston North
> New Zealand
> "Quote me as saying I was misquoted " - Groucho Marx
> &~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Arthur Gilmour PhD                    email:
Senior Research Scientist (Biometrics)                 fax: <61> 2 6391 3899
NSW Agriculture                                             <61> 2 6391 3922
Orange Agricultural Institute               telephone work: <61> 2 6391 3815
Forest Rd, ORANGE, 2800, AUSTRALIA                    home: <61> 2 6362 0046

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