The paper examines the effect of trend productivity growth on the determinacy and learnability of equilibria under alternative monetary policy rules. It shows that under a policy rule that responds to current period inflation and the output gap a higher trend growth rate relaxes the conditions...

We examine global economic dynamics under learning in a New Keynesian model in which the interest-rate rule is subject to the zero lower bound. Under normal monetary and fiscal policy, the intended steady state is locally but not globally stable. Large pessimistic shocks to expectations can lead...

We analyze the implications of changes in the trend growth rate for optimal monetary policy in the presence of search and matching unemployment. We show that trend growth in itself does not generate a trade-off for the monetary authority, but that it interacts importantly with the inefficiencies...

Available evidence supports the view that growth is faster in more open economies. In order to analyze the implications of openness and growth on determinacy and learnability of worldwide rational expectations equilibria we develop a two-country New Keynesian model with growth. We analyze these...

We analyze determinacy and stability under learning (E-stability) of rational expectations equilibria in the Blanchard and Galí (2006, 2008) New-Keynesian model of inflation and unemployment, where labor market frictions due to costs of hiring workers play an important role. We derive results...

We analyze optimal monetary policy when a central bank has to learn about an unknown coefficient that determines the effect of surprise inflation on aggregate demand. We derive the optimal policy under active learning and compare it to two limiting cases---certainty equivalence policy and...

We study how the use of judgement or add-factorsʺ in macroeconomic 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 standard macroeconomic...

A fundamentals based monetary policy rule, which would be the optimal monetary policy without commitment when private agents have perfectly rational expectations, is unstable if in fact these agents follow standard adaptive learning rules. This problem can be overcome if private expectations are...