[R-sig-ME] Using a custom random effects design matrix in MCMCglmm

[r_1470]

Hi,
 Does anyone know if it's possible to use a custom random effects design matrix with MCMCglmm, e.g. by replacing the model$Z object with a custom object in the same format before passing it to the MCMC? 
To give more background, I have a multi-membership model with an interaction for each element, but the 'mm' argument in MCMCglmm doesn't allow interactions. There's a partial solution using the 'mult.memb' function, but I also need to associate the multi-membership model with the inverse relationship matrix using 'ginverse', and I haven't found a solution with mult.memb that allows this.
I've worked out what the correct design matrix should be, but just can't figure out how to use it. Making a custom 'MCMCglmm2' function with a new argument for using a custom Z object didn't work, presumably because it failed to connect to the C code for the MCMC. If that part worked, I think it would run.

Best wishes,
Richard.
	[[alternative HTML version deleted]]