[R-sig-ME] UNSOLVED: Re: lme4 or other open source mixed model package code equivalent to asreml-R

[Ben Bolker]

David Duffy <David.Duffy at ...> writes:

> 
> On Fri, 18 Nov 2011, Ben Bolker wrote:

  [snip] 

> Well, I do not have any experience carrying out spatial modelling, but it 
> did seem to me that the covariances arising from the separable AR1xAR1 
> model must be have a close resemblance to some of the other standard 
> models.  Specifically, page 85 of Haskard's thesis
> 
> http://digital.library.adelaide.edu.au/dspace/bitstream/2440/47972/1/02whole.pdf
> 
> seems to imply it is equivalent to a anisotropic Matern model.  This is 
> offered by the spatialCovariance package, AIUI.
> 
> It took me a while to understand that the example dataset is the Wheat2 
> data from the nmle package, which Pinheiro and Bates (2000, P 263) analyse 
> using spherical and rational quadratic models.  I am unsure if the OP is 
> particularly interested in the exact models he chose for his example, or 
> whether one can generally match ASREML's functionality, or has data that 
> might be comfortably analysed usibg existing lme correlation structures.

  Dave Fournier has posted a solution using AD Model Builder at

http://groups.google.com/group/admb-users/browse_thread/
   thread/96bf76c9f578650b

(sorry, URL broken to make Gmane happy) that tackles (almost) this problem (it
actually
does a spatial GLMM -- a Poisson model layered on the AR1 x AR1
Gaussian random field).

  Ben Bolker