The fact is, economics is not an experimental science and cannot be. "Natural" experiments and "quasi" experiments are not in fact experiments. They are rhetorical devices that are often invoked to avoid having to confront real econometric difficulties. Natural, quasi-, and computational...

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...

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...

It is now widely understood how to obtain first-order accurate approximations to the solution to a dynamic, stochastic general equilibrium model (DSGE model). Such solutions are fairly easy to construct and useful for a wide variety of purposes. They are likely to be accurate enough to be a...

The literature applying information-theoretic ideas to economics has so far considered only Gaussian uncertainty. Ex post Gaussian uncertainty can be justified as optimal when the associated optimization problem is linear-quadratic, but the literature has often assumed Gaussian uncertainty even...

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...

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...