Longue mais très intéressante interview de Kenneth Rogoff sur la crise financière et plusieurs questions macroéconomiques majeures. Je retiendrai la conclusion sur l’état de la macroéconomie et de l’économie financière :
« Macro and finance have been dominated by the perfect markets paradigm because it’s very convenient, and we got a lot of nice results and it’s been constructive. But I think the advocates of that approach have all too often argued, « Well, OK, we know markets aren’t perfect, but it’s hard to do better than this in a constructive way. Besides, whatever we’re missing maybe isn’t so important. »
But for many policy issues and especially for monetary policy, one cannot work only with models featuring perfect financial markets. Consider the fact that a lot of the inflation targeting literature employs models with perfect financial markets. So it’s not exactly amazing that scholars wedded to this approach find that there is never a good case for looking at housing prices, above and beyond their effects on output and inflation. Yet empirical researchers have long argued that there is considerable danger whenever asset price inflations are accompanied by sharp rises in indebtedness. The doctrinaire inflation targeters dismissed this perspective, but hopefully they are rethinking things now. This is another reason why optimal inflation targeting models are simply too fragile.
No doubt, young economists will figure out better models for monetary policy. Of course, we already have models embodying financial market imperfections. For example, we have a lot of such models in international finance, including especially the literature on sovereign debt and default. Unfortunately, they can be very tough to work with practically and do not lend themselves to the same kind of flexible empirical analysis as the standard New Keynesian models (with perfect financial markets) now widely in use.
Fortunately, the financial crisis is going to stimulate a lot of further research seeking better practical monetary policy models. Happily, at the same time as the financial crisis has confronted us with fascinating new problems, it will encourage a lot of talented young students to go into economics research instead of the investment banking sector, where they might have gone until recently [laughter] ».