%A Emre Yilmaz %A Thai Son Hoang %T Development of Rabin's Choice Coordination Algorithm in Event-B %X The paper reports our investigation on tool support for the integration of qualitative probabilistic reasoning into Event-B. In the process, we formalise a non-trivial algorithm, namely Rabin's choice coordination. Our correctness reasoning is a combination of termination proofs in terms of probabilistic convergence and standard invariant techniques. Moreover, we describe how qualitative probabilistic reasoning can be maintained during refinement. %C Dusseldorf, Germany %I University of D?sseldorf %L deploy258