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Unacceptibly high autocorrelation in MCMCglmm

HI,

It looks like the probit has underflowed/overflowed - you can check  
this by saving the latent variables and looking to see whether the  
range of the absolute values exceeds 7 (See Section 8.08 of  
CourseNotes).

This can happen with weak priors and (near) complete separation and/or  
with weak priors for effects that are heavily confounded.

I'm not sure how to proceed with underflow/overflow problems  
generally.  I could terminate the procedure, or I could truncate the  
latent variables at their overflow/underflow points. The latter is  
used by some WinBUGS users, but then WinBUGS handles the fact that the  
response is from a truncated normal not a normal - something which  
would be hard to program in MCMCglmm. Any thoughts would be useful.

Cheers,

Jarrod



Quoting Stuart Luppescu <slu at ccsr.uchicago.edu> on Fri, 16 Mar 2012  
17:38:15 -0500: