[R-sig-ME] lmer and semi-definite covariance matrices for randomeffects

[David Duffy]

On Wed, 3 Apr 2013, Gabriel Baud-Bovy wrote:

> Dear all,
>
> I am trying to use pedigreemm approach to analyze twin data. The model
> includes semidefinite covariance matrices for random effects of the
> form  sigma*corA

Not completely satisfactory, but we just added a ridge constant.

| David Duffy (MBBS PhD)                                         ,-_|\
| email: davidD at qimr.edu.au  ph: INT+61+7+3362-0217 fax: -0101  /     *
| Epidemiology Unit, Queensland Institute of Medical Research   \_,-._/
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