We discuss a time invariant policy which delivers the unconditionally optimal outcomes in purely forward-looking models and Ramsey outcomes in purely backward-looking models. This policy is a product of interaction between two institutions with distinct responsibilities. Motivated by Brendon and Ellison (2015), we think of them as arms of government. One institution is responsible for ‘forward guidance’, setting rules which are necessary and sufficient to determine private expectations. The second institution implements optimal policy taking expectations as given. The forward guidance rules are designed to maximise the unconditional expectation of the social objectives.

我们讨论了一种时间不变策略，它在纯前瞻性模型中提供无条件最优结果，在纯后视模型中提供 Ramsey 结果。该政策是具有不同职责的两个机构之间相互作用的产物。受 Brendon 和 Ellison (2015) 的启发，我们将它们视为政府的武器。一个机构负责“前瞻性指导”，制定必要和充分的规则来确定私人期望。第二个机构以既定的期望实施最优政策。前瞻性指导规则旨在最大化社会目标的无条件期望。