Electricity and Information Technology (IT) are perhaps the two most important general purpose technologies (GPTs) to date. We analyze how the U.S. economy reacted to them. The Electricity and IT eras are similar, but also differ in several important ways. Electrification was more broadly...

The usual explanation for why the producers of a given product use different technologies involves "vintage-capital": A firm understands the frontier technology, but can still prefer an older, less efficient technology in which it has made specific physical and human capital investments. This...

This paper studies how random product innovations affect the time series properties of aggregates. It posits that recurring inventions of new intermediate goods differ in quality, and that their usage spreads gradually through the economy. It examines how fluctuations in per capita GNP are...

One usually accounts for output growth in terms of the growth of the primary inputs: labor, physical capital, and possibly human capital. In this paper we account for growth with labor and with intermediate goods. Because we have no measures of the extent of adoption of most intermediate goods...