关键词: 理性预期模型, 宏观经济政策, 前期有效, 中美政策效应比较

Abstract: By classifying the validity of macroeconomic policy into early-phase, current-phase and last-phase effectiveness based on the review of the rational expectation model, it finds that the macroeconomic policies are effective in general even under the framework of rational expectation theory. The difference is that the macroeconomic policies are effective at early phase under the framework of rational expectation theory. This paper uses the actual data from both China and the United States as samples to test the effectiveness of monetary policy with an empirical analytical approach. The result shows that the monetary policy in China is not only effective at the early but also at the last phases while in the United States only effective at the early phase and ineffective at the last phase. The causes come from the differences in the ways of transmission of policy signals and of formation of public expectations on monetary policy. But whatever in which way the public expectations on macroeconomic policies are, it will exert an impact on macroeconomic operation and the economic policies are fundamental in any way.

Key words: Rational Expectation Model, Macroeconomic Policy, Effective at Early Phase, Comparison of Policy Effects in China and the US