Thank-you for all your help! This discussion got my mind to the point where I could see how to see how the variance components were stored.
For anyone reading this thread in future … two things really enabled me to figure this out (not counting the actual answer!).
- Look at the source code (for the version you are using).
- fieldnames(typeof(object)) and then looking at each field can be helpful. In my case, the variance components are stored sigma space and have to be multiplied by the residual sigma to put them on their natural scale. For the ith component the variance was (sigma[i]*resid_sigma)^2. (Which you can see in the original response).