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...

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...