Reproducing with elementary resources the correlations that arise when a
quantum system is measured (quantum state simulation), allows one to get
insight on the operational and computational power of quantum correlations. We
propose a family of models that can simulate von Neumann measurements in the
x-y plane of the Bloch sphere on n-partite GHZ states using only bipartite
nonlocal boxes. For the tripartite and fourpartite states, the models use only
bipartite nonlocal boxes; they can be translated into classical communication
schemes with finite average communication cost.Comment: 15 pages, 4 figures, published versio