I would like to clarify how JMP handles this specific case.
I am using JMP Student Edition 19.1.1 and fitting a negative binomial model with a log link in the Generalized Linear Mixed Model personality, without any random effects or offset. My response is the daily mean number of newly diseased leaflets per plant across five plants, including noninteger values resulting from averaging and allocation of counts between survey dates.
I understand that, without random effects, the model has the structure of a generalized linear model. However, JMP reports “−2 Residual Log Pseudo-Likelihood.”
Could you please clarify the following?
- In this specific setting, how are the negative binomial dispersion parameter and the reported −2 Residual Log Pseudo-Likelihood calculated? Is this statistic based on the actual negative binomial likelihood or on the residual likelihood of a linearized model?
- Can this statistic be compared between models fitted to exactly the same response values and rows, but using different weather predictors or different interaction terms? Does having the same number of parameters make such comparisons valid?
- If these comparisons are not valid, should I refit the models using Negative Binomial and Maximum Likelihood in the Generalized Regression personality and compare AICc?
A reference to the relevant JMP documentation or calculation formula would be very helpful. Thank you.