Re: Bending
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Re: Bending



Hi,

On Sun, 9 Jul 2000, C. Balde wrote:

> Dear Arthur,
> 
> I'm trying to fit a multivariate model (3-variate) but I get some
> problems (the problem appears when I add the third variable). The fact
> is that in some iterations ASREML modifies the variance components with
> Bending and finally the LogL gets into a cycle. I tried the model with
> and without scaling the variables. I want you to know that the third
> variable is a function of the other two variables.
> 
> Is there any way to solve this problem ?
> I tried scaling the variables, reducing the stepsize, changing initial
> values, increasing the number of iterations, etc.
> 
> Regards,
> Hermann
> 

This is not a 'problem'.
There are some options: !GU  may help.
See page 84 of the Jul 6 manual where it is suggested to try different
starting values.  See also page 103.

You probably also should look at the eigenvalues of the
variance/covariance matrix. It may make no sense to use the third variate.

Regards,
Bruce

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