A key question in economic research and policymaking is to what extent one can use simplified models. This paper addresses this question by comparing the results of two learning-to-forecast laboratory experiments: one design based on the reduced form of a New-Keynesian model; and one design...

We study how the use of judgment or "add-factors" in forecasting may disturb the set of equilibrium outcomes when agents learn using recursive methods. We isolate conditions under which new phenomena, which we call exuberance equilibria, can exist in a standard self-referential environment....