Learning and Equilibrium Selection in a Monetary Overlapping Generations Model with Sticky Prices
研究货币世代交叠模型中代理人的适应性学习，发现粘性价格能解决灵活价格下的多重暂时均衡问题，并稳健地选择确定的货币稳态，对理解学习在均衡选择中的作用有参考价值。
We study adaptive learning in a monetary overlapping generations model with sticky prices and monopolistic competition for the case where learning agents observe current endogenous variables. Observability of current variables is essential for informational consistency of the learning setup with the model setup but generates multiple temporary equilibria when prices are flexible and prevents a straightforward construction of the learning dynamics. Sticky prices overcome this problem by avoiding simultaneity between prices and price expectations. Adaptive learning then robustly selects the determinate (monetary) steady state independent from the degree of imperfect competition. The indeterminate (non-monetary) steady state and non-stationary equilibria are never stable. Stability in a deterministic version of the model may differ because perfect foresight equilibria can be the limit of restricted perceptions equilibria of the stochastic economy with vanishing noise and thereby inherit different stability properties. This discontinuity at the zero variance of shocks suggests one should analyse learning in stochastic models. Copyright 2003, Wiley-Blackwell.