Economic inequality is higher today than it has been since 1939, as measured by both the wage structure and wealth inequality. But the comparison between 1939 and 1999 is largely made out of necessity; the 1940 U.S. population census was the first to inquire of wage and salary income and...

This paper examines shifts over time in the relative demand for skilled labor in the United States. Although de-skilling in the conventional sense did occur overall in nineteenth century manufacturing, a more nuanced picture is that occupations "hollowed out": the share of "middle-skill" jobs -...

In this paper we derive a model of aggregate investment that builds from the lumpy microeconomic behavior of firms facing stochastic fixed adjustment costs. Instead of the standard (S,s) bands, firms' optimal adjustment policies are probabilistic, with a probability of adjusting (adjustment...

This paper develops a method for joint estimation of both the degree of internal returns to scale and the extent of external economies. We apply the method in estimating returns to scale indexes for U.S. manufacturing industries at the two-digit level. Overall, we find that only three of the...