Yesterday the New York Times published an article about simulations of the effects of fiscal stimulus packages and financial interventions using an old Keynesian model. The simulations were reported in an unpublished working paper by Alan Blinder and Mark Zandi. I offered a short quote for the article saying simply that the reported results were completely different from my own empirical work on the policy responses to the crisis.
I have now had a chance to read the paper and have more to say. First, I do not think the paper tells us anything about the impact of these policies. It simply runs the policies through a model (Zandi’s model) and reports what the model says would happen. It does not look at what actually happened, and it does not look at other models, only Zandi’s own model. I have explained the defects with this type of exercise many times, most recently in testimony at a July 1, 2010 House Budget Committee hearing where Zandi also appeared. I showed that the results are entirely dependent on the model: old Keynesian models (such as Zandi’s model) show large effects and new Keynesian models show small effects. So there is nothing new in the fiscal stimulus part of this paper.
Second, I looked at how they assessed the impact of the financial market interventions. Again they do not directly assess the interventions. They just simulate the model with and without the interventions. They say that they have equations in the model which include the financial interventions as variables, but they do not report the size or significance of the coefficients or how they obtained them.
Third, the working paper makes no mention of previously published papers in the literature which get different results. It is rather standard in research to provide a literature review and to explain why the results are different from previous published papers. For the record there are different results in papers by John Cogan, Volcker Wieland, Tobias Cwik and me in the Journal of Economic Dynamics and Control, by John Williams and me in the American Economic Journal; Macroeconomics, or by me published by the Bank of Canada or the St. Louis Fed
Finally, when I read the paper I discovered in an appendix that Blinder and Zandi find that policy was not as good as the model shows and was in fact quite poor when one does a more comprehensive evaluation. They say in Appendix A that “Poor policymaking prior to TARP helped turn a serious but seemingly controllable financial crisis into an out-of-control panic. Policymakers’ uneven treatment of troubled institutions (e.g., saving Bear Stearns but letting Lehman fail) created confusion about the rules of the game and uncertainty among shareholders, who dumped their stock, and creditors, who demanded more collateral to provide liquidity to financial institutions.” I completely agree with this statement, but how can one then argue that policy intervnetions worked, when, in fact, viewed in their entirety they caused the problem?