Comparison of ADMB and WinBUGS modelling approach for simple occupancy model. This is also a comparison of Bayesian and frequentist modelling.
The presence of animals (or some other object) at a site is determined by a latent indicator variable z:
z = 1 presence of animlas
z = 0 absence
Conditioinally on z = 1, the number of animals y follows a binomial distribution
The following annotated code show how such a model is implemented in WinBUGS and ADMB, and highlights differences.