Social Learning and Monetary Policy at the Effective Lower Bound
构建模型解释大衰退后为何未出现通缩以及随后无通胀的复苏，机制是异质性预期可能长期偏离央行目标并协调在持续低于目标的路径上，央行通过沟通可降低福利成本但可能失去可信度。
Abstract 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.