Trouble getting se.fit and confidence intervals using clmm2 from ordinal package

Question

I'm using clmm function from ordinal package in R in order to fit cumulative mixed models to my data. It worked fine until I tried to get predicted probabilities. I can't get either SE or confidence intervals by specifying se.fit=TRUE and interval=TRUE. It looks like this:

mod1<-clmm2(response~X0+X1+X2+X3+X4+X5+X7+X0*X2*X3+X2*X3*X4+X0:X4, random=X6, 
                      data=df,link ="logistic", threshold ="flexible", 
                      Hess=TRUE, nAGQ=7)

As you can see there a bunch of interaction there (all important). I've tried to create a dummy dataset for my problem to be reproducible but clmm can't achieve convergence with a simpler dataset. I took the wine dataset included in the package ordinal and did some changes with the formula to mimic my own (I don't think it makes any sense though):

library(ordinal)
data(wine)
fm1 <- clmm2(rating ~ temp + contact+bottle+temp:contact:bottle+temp:contact+ temp:bottle+bottle:contact,random=judge, data=wine,link ="logistic", threshold ="flexible", 
         Hess=TRUE, nAGQ=7)

head(do.call("cbind", predict(fm1, se.fit=TRUE, interval=TRUE)))

And then I get this error:

Error in head(do.call("cbind", predict(fm1, se.fit = TRUE, interval = TRUE))) : 
 error in evaluating the argument 'x' in selecting a method for function 'head' : Erreur dans do.call("cbind", predict(fm1, se.fit = TRUE, interval = TRUE)) : second argument must be a list

My guess is that predict does'nt even compute SE and IC in a case like this. Does anybody knows why? Is there anyway to get those values?

Thanks a lot!

Answer 1

The predict method for clmm2 objects does not offer std-errors. See its help page. This is in keeping with the usual practice of R package authors when dealing with mixed effects models.