This paper develops a model that jointly accounts for the missing disinflation in the wake of the Great Recession and the subsequently observed inflation‐less recovery. The key mechanism works through heterogeneous expectations that may durably lose their anchoring to the central bank (CB)'s target and coordinate on particularly persistent below‐target paths. The welfare cost associated with persistent low inflation may be reduced if the CB announces to the agents its target or its own inflation forecasts, as communication helps coordinate expectations. However, the CB may lose its credibility whenever its announcements become decoupled from actual inflation.

中文翻译：

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有效下限的社会学习和货币政策

本文开发了一个模型，共同解释了大衰退后缺失的通货紧缩以及随后观察到的无通胀复苏。关键机制通过异质预期发挥作用，这些预期可能会永久失去对央行（CB）目标的锚定，并在特别持续低于目标的路径上进行协调。如果中央银行向代理人宣布其目标或自己的通胀预测，则与持续低通胀相关的福利成本可能会降低，因为沟通有助于协调预期。然而，只要央行的公告与实际通胀脱钩，央行就可能会失去可信度。