摘要：Carlsson and van Damme (1991, 93) presented a notion of a global game, which is an
incomplete information game where the actual payo# structure is a#ected by a realization of a
common shock and where each player gets noisy private information of the shock. For
n-person symmetric games with two possible actions characterized by strategic complementar-
ity, they showed that equilibrium play in a global game with vanishing noise is uniquely
determined. The concept of global games is important not only as a theory of the most refined
notion of equilibrium but also as a theory of coordination failures under private information.
From this viewpoint, this paper makes the theory of global games more general and more
applicable to such problems. The implications of the theory of global games are investigated in
two specific models: a speculative attack model and a network externality model. It is shown
that both the monetary authority in the speculative attack model and the central planner in the
network externality model will prefer the equilibrium in a global game with small noise to the
worst equilibrium in the corresponding complete information game. Therefore, they will
welcome the existence of small noise, if they apply mini-max principle to multiple equilibrium
problems.
