Comments

For nbinom2 the dispersion parameter is denoted by \(\theta\), while for nbinom1 it is denoted by \(\alpha\). What these parameters have in common is that they affect the mean-variance relationship. For more details see: 8: Dispersion modelling.

Citations

Brooks, M. E., Kristensen, K., Darrigo, M. R., Rubim, P., Uriarte, M., Bruna, E., & Bolker, B. M. (2019). Statistical modeling of patterns in annual reproductive rates. Ecology, 100(7), 1–7. https://www.jstor.org/stable/26727162

Hardin, J.W. and Hilbe, J.M. (2007) Generalized Linear Models and Extensions. A Stata Press Publication, StatCorp LP, Texas.