Computing time-consistent equilibria: A perturbation approach
针对时间不一致性问题（如最优财政与货币政策），提出一种摄动求解方法，避免投影法的维数灾难，适用于稳态非有效的模型。
Time-consistency is a key feature of many important policy problems, such as those relating to optimal fiscal policy, optimal monetary policy, macro-prudential policy, and sovereign lending. It is also important for private-sector decision-making through mechanisms such as quasi-geometric discounting. These problems are generally solved using some form of projection method. The difficulty with projection methods is that their computational complexity increases rapidly with the number of state variables, limiting the sophistication of the models that can be solved. This paper develops a perturbation method for solving models with time-inconsistency. The method operates on a model’s (generalized) Euler equations; it does not require forming a quadratic approximation to household welfare and it does not require that the model’s steady state be efficient. We illustrate the method and its applicability to different environments by applying it to a range of models featuring time-inconsistency.