This paper estimates a New Keynesian model extended to include heterogeneous expectations: consumers and firms form either rational or boundedly-rational expectations. The inclusion of heterogeneous expectations alters the determinacy properties of the model, with the details of expectations potentially becoming more influential than the Taylor principle for equilibrium stability.

The model is estimated with Bayesian techniques, using rolling windows and allowing the parameters to fall both in the determinacy and indeterminacy regions. The estimates reveal large shares of agents who depart from rational expectations. Heterogeneous expectations are decisively preferred by the data everywhere in the sample.

Finally, the paper revisits the narrative that sees postwar US macroeconomic data as consistent with indeterminacy in the pre-1979 sample, with a switch to determinacy starting in the early 1980s, and it shows that it is overall robust to inclusion of heterogeneous expectations.

本文估计了一种新的凯恩斯主义模型，该模型扩展到包括异类期望：消费者和企业形成理性或有限理性的期望。包含异类期望会改变模型的确定性，期望的细节可能比平衡稳定性的泰勒原理更具影响力。

该模型是使用贝叶斯技术，使用滚动窗口并允许参数同时在确定性区域和不确定性区域内进行估计的。估计值显示出有大量代理商背离了理性预期。样本中各处的数据都决定性地使用异类期望。

最后，本文重新审视了将战后美国宏观经济数据与1979年之前样本中的不确定性相一致的说法，并从1980年代初开始转向确定性，它表明，将异类预期包括在内总体上是稳健的。