Anchoring Economic Predictions in Common Knowledge

The paper examines within a uni…ed methodology expectational coordination in a series of economic models. The methodology views the predictions associated with the Rational Expectations Hypothesis as reasonable whenever they can be derived from more basic Common Knowledge hypothesis. The paper successively considers a simple non noisy N-dimensional model, standard models with " intrinsic " uncertainty, reference intertemporal models with in…nite horizon. It reviews existing results and suggests new ones. It translates the formal results into looser but economically intuitive statements , whose robustness, in the present state of knowledge, is tentatively ascertained.