This paper explores Knightian model uncertainty about dynamic misspecification as a possible explanation of the considerable difference between estimated interest rate rules and optimal feedback descriptions of monetary policy. In the literature on robust control, Knightian uncertainty about a...

We study 30 vintages of FRB/US, the principal macro model used by the Federal Reserve Board staff for forecasting and policy analysis. To do this, we exploit archives of the model code, coefficients, baseline databases and stochastic shock sets stored after each FOMC meeting from the model's...