The Keynesian model has some clear, practical insights about how to think about fiscal policy during economic downturns. But are those insights true?
One approach to answering this question is to examine the data using the techniques of time-series econometrics without imposing much a priori theory. For monetary policy, there is a large literature that does this; for fiscal policy, the literature is smaller but growing. The results from this exercise, however, do not always confirm the predictions from textbook Keynesian models. ...
I am not sure how convinced I am by these findings. And even if they are correct, I am not sure what model I should use to explain them and to what extent that model would apply to the extraordinary economic circumstances we now face. At the very least, these puzzles should give us reason to pause when using the Keynesian framework for policy analysis. There is still a lot about macroeconomics that remains deeply puzzling.
Tuesday, December 2, 2008
Here's a post by Mankiw on some recent studies that question the effectiveness of fiscal policy as a tool for aggregate demand management. His main point: