Recently, I have been struggling with simulating data from complex hierarchical models. After several unsuccessful attempts in R, I remembered the good old times when I was using WinBUGS (more than 10 years already!) and the possibility to simulate data with it. I'm using Jags now, and a quick search in Google with 'simulating data with jags' led me to a complex example and a simple example.
Here, I illustrate the possibility to use Jags to simulate data with two examples that might be of interest to population ecologists: first a linear regression, second a Cormack-Jolly-Seber capture-recapture model to estimate animal survival (formulated as a state-space model).
Simulating data with Jags is convenient because you can use (almost) the same code for simulation and inference, and you can carry out simulation studies (bias, precision, interval coverage) in the same environment (namely Jags).