Sunday, July 12, 2009

Modern macro even Paul Krugman will love

Lately, Paul Krugman has been dissing modern macroeconomics, mainly because many macroeconomists do not agree with his conclusions about fiscal policy. This new paper by Marty Eichenbaum, Larry Christiano, and Sergio Rebelo should, however, make Paul happy. They report large fiscal policy multipliers in a new Keynesian DSGE model when the economy is at the zero interest lower bound.

An open question: How can the results in this paper be reconciled with results by John Cogan, Tobias Cwik, John Taylor, and Volker Wieland, who seem to perform a similar policy simulation in a similar model but reach a very different conclusion? Are there subtle differences in the models? Or subtle differences in the policy experiments? Or did one team simply make a mistake of some sort?

Figuring out why these two prominent teams of researchers come to opposite conclusions about fiscal policy multipliers, and which conclusion is more applicable to actual policy, would be a good paper topic for an ambitious grad student.