The tick (as in clock tick) is the unit of time against which agent actions etc. are scheduled. The final tick is just the last time anything happened in the model. You can use the scheduling API to schedule agent behavior (i.e. any class method) for some specific time. Often this is just some behavior an agent does over and over again so its scheduled starting at tick 1 and for every tick thereafter. There's no direct relationship between a tick and movement. How far an agent moves depends on the specifics of an agent. For example, you could code your agent to move 2, 4, or whatever grid cells per tick. That said, we do automate some behavior w/r to ticks such that a user doesn't necessarily have to use the scheduling API. If you could say more about your model (perhaps you are using ReLogo?), we can say more about how "tick" relates to your model.
Thank you very for your exhaustive reply. I am using the Java version of Repast.
In my model I am simulating an evacuation from a building, of course a critical parameter in this situation is the time, then to elaborate my simulation's results, I need to parametrize properly the ticks in terms of seconds.
P.S. how can I set up how many grid cells an agent moves each tick ??
Any advices would be more than welcome.
Thank you very much.