If macroeconomic models are to be useful in policy-making, where uncertainty is pervasive, the models must be treated as probability models, whether formally or informally. Use of explicit probability models allows us to learn systematically from past mistakes, to integrate model-based...

A multivariate model, identifying monetary policy and allowing for simultaneity and regime switching in coefficients and variances, is confronted with US data since 1959. The best fit is with a version that allows time variation in structural disturbance variances only. Among versions that allow...

The Euro was created at a time when the conventional view was that a central bank could control inflation by controlling the money supply and that fiscal policy’s interaction with monetary policy took the form of attempts to get the central bank to finance government debt. With a sufficiently...

I have written several papers for BPEA (2002; 1996; 1982) looking at the relation of multiple equation quantitative economic models to the process of monetary policy making. When the first of these papers was written, the impact of the rational expectations critique in undermining academic interest in...

Several aspects of the difficulties of policy at the zero lower bound are discussed: The difficulty of credible commitment to higher future inflation, as most New Keynesian models imply is necessary; the need for fiscal and monetary policy coordination; the pitfalls in the taking of quasi-fiscal...

The inflation of the 1970s in the US is often discussed as if the only type of policy action that could have prevented the inflation were monetary policy actions and the only type of policy errors that might have induced the inflation were monetary policy errors. Yet fiscal policy underwent...

Rational inattention theory is economic theory that recognizes that people have finite information-processing capacity, in the sense of Shannon and engineering information theory. This approach is still in the early stages of development, but it promises to provide a unified explanation for some...

Interview with the 2011 Laureates in Economic Sciences Thomas J. Sargent and Christopher A. Sims, 6 December 2011. The interviewer is Adam Smith, Editorial Director of Nobel Media.