[R-sig-ME] MCMCglmm Bivariate Binary Model

[Chuck Cleland]

Hi All,

  I attempted to fit a bivariate binary model similar to the example in
the Tutorial:

prior = list(R = list(V = diag(2), n = 0, fix = 2),
             G = list(G1 = list(V = diag(2), n = 1)))

model5 <- MCMCglmm(cbind(ANYHR, ANYPO) ~ trait - 1, random =
~us(trait):PROGRAM, rcov = ~idh(trait):units, family=c("categorical",
"categorical"), data = radars, prior = prior, verbose = FALSE)

Error in MCMCglmm(cbind(ANYHR, ANYPO) ~ trait - 1, random =
~us(trait):PROGRAM,  :
  ill-conditioned G/R structure: use proper priors if you haven't or
rescale data if you have

  In this dataset, one of the four cells in the 2x2 table is empty:

   Cell Contents
|-------------------------|
|                   Count |
|-------------------------|

Total Observations in Table:  21335

             | ANYPO
       ANYHR |        0  |        1  | Row Total |
-------------|-----------|-----------|-----------|
           0 |        0  |     8999  |     8999  |
-------------|-----------|-----------|-----------|
           1 |     6458  |     5878  |    12336  |
-------------|-----------|-----------|-----------|
Column Total |     6458  |    14877  |    21335  |
-------------|-----------|-----------|-----------|

  Is there a way to change the specification for prior to make this work?

thanks,

Chuck

-- 
Chuck Cleland, Ph.D.
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