  A novel, scalable, on-the-fly model-checking procedure is presented to verify
bounded PCTL properties of selected individuals in the context of very large
systems of independent interacting objects. The proposed procedure combines
on-the-fly model checking techniques with deterministic mean-field
approximation in discrete time. The asymptotic correctness of the procedure is
shown and some results of the application of a prototype implementation of the
FlyFast model-checker are presented.
