A Model of Near-Rational Exuberance

We study how the use of judgement 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. Local indeterminacy is not a requirement for existence. We construct a simple asset pricing example and find that exuberance equilibria, when they exist, can be extremely volatile relative to fundamental equilibria. learning, recurrent hyperinflations, and macroeconomic policy to combat liquidity traps and deflation.Learning, expectations, excess volatility, bounded rationality.