Tony, it's not too tough at all. All you need is a function which picks a random interval of time based on your probabilistic distribution. Then in the agent's step() method, the first thing you say something like: double delta = random_interval_of_time(); state.schedule.scheduleOnceIn(delta, this); And you're done! If you want a more abstract thing, we can put together a class which does arbitrary repeats. Like Repast, you can also replace or subclass MASON's schedule. For example, we could modify the Repeat inner class to call a function in Schedule to get the interval to step by rather than a fixed interval, and then you just override that function to provide the interval you like. Sean On Jun 30, 2011, at 1:54 PM, Tony Bigbee wrote: > Hi, > > There may only be one or two MASON core team members on this list > who can answer this question, but: > > I've inherited some code in an internal project that uses a > subclassed AbstractAction from Repast so that things are stepped > according to a probabilistic distribution--instead of stepping at > precise intervals, such as every 10 ticks, scheduled entities are > stepped, on average, every 10 ticks: > > "GeomAction provides an IAction that repeats at intervals drawn from > the geometric distribution. The interval parameter passed into the > constructor is the probability that the action occurs in one > tick.The event [AbstractAction] converts the interval to log(1-P) to > increase efficiency in computing the interval. The interval for > rescheduling will be ceiling(log(U)/log(1-P)) where U is a draw from > the uniform random distribution between 0 and 1.0" > > Repast allows you to replace their "schedule" with a custom version, > and ours creates GeomAction instances as described above. They use > reflection and annotated methods rather than a step() approach like > MASON, but that's not the important part of this. > > Is geometric scheduling would be something that I could implement in > MASON and what the scope might entail? I would like to consider > switching our project to MASON.