I'm attempting to run a GZLM with a poisson distribution and a nested term in SPSS 16. In the GZLM Model window you can build nested terms but this doesn't seem to be working for me.
I have 3 categorical terms (DG, DS, & DC) and 4 scale terms (dist, slope, SC, & CC) that are all nested within another categorical term (Trans). I have been constructing the model so that the terms look like this:
When I run this model the output is mostly absent and I think this is because with the nested term there are hundreds of parameter estimates (I believe I'm using up all my dfs, but I could be wrong about that).
Any suggestions about what I am doing wrong, or what I should be doing to make this work?