We review an emerging body of work by physicists addressing questions of economic organization and function. We suggest that, beyond simply employing models familiar from physics to economic observables, remarkable regularities in economic data may suggest parts of social order that can usefully...

I have been doing research in macroeconomics since the late 1960s, almost 50 years. In this paper I pause and take stock. The paper is part personal reflections on macroeconometric modeling, part a road map of the techniques of macroeconometric modeling, and part comments on what I think I have...

There have been a number of recent papers arguing that there has been considerable convergence in macro research and to the good. This paper considers the question whether what has been converged to is good. Has progress been made in understanding how the macro economy works?

Some challenges for econometric research on trending time are discussed in relation to some perceived needs of macroeconomics and macroeconomic policy making.

The sensitivity of U.S. aggregate investment to shocks is procyclical: the response upon impact increases by approximately 50% from the trough to the peak of the business cycle. This feature of the data follows naturally from a DSGE model with lumpy microeconomic capital adjustment. Beyond...

This paper examines how much structural change there was in the U.S. economy in the last half of the 1990s. The results are consistent with the hypothesis that there was only one major structural change, namely the huge increase in stock prices relative to earnings. All other large changes can...

Microeconomic lumpiness matters for macroeconomics. According to our DSGE model, it explains roughly 60% of the smoothing in the investment response to aggregate shocks. The remaining 40% is explained by general equilibrium forces. The central role played by micro frictions for aggregate...

In an incomplete asset market, firms assign values to investment plans by projecting their payoffs on the span of the payoffs of marketed assets; equivalently, firms employ the Capital Asset Pricing Model. This is a criterion that does not require firms to possess information, such as the...