Improvements in the software that provides hardware management, user interface and platform functions have played a central role in the growth and transformation of the personal computer (PC) industry. Several forces shape the design of these 'operating system' products and propel their...

We compare "real business cycle" and increasing returns models of economic fluctuations. In these models, business cycles are driven by productivity changes resulting either from technology shocks or from crucial building blocks that give both types of models hope of fitting the data. These...

Our model of growth departs from both the Malthusian and neoclassical approaches by including investments in human capital. We assume, crucially, that rates of return on human capital investments rise, rather than, decline, as the stock of human capital increases, until the stock becomes large....

We describe an economy where a durable good is produced with an increasing returns to scale technology. Equilibria in this economy take the form of business cycles in which consumption fluctuates too much and is too low on average. A 2-sector version of this economy with imperfect credit and...

We analyze entry, pricing and product design in a model with differentiated products. Under plausible conditions, entry into an initially monopolized market leads to higher prices for some, possibly all, consumers. Entry can induce a misallocation of goods to consumers, segment the market in a...

U.S. beef cattle stocks are among the most periodic time-series in economics. A theory of cattle cycles is constructed, based upon rational breeding stock inventory decisions in the presence of gestation and maturation delays between production and consumption. The low fertility rates of cows...

We present a model of trade in which similar countries trade more with each other than very different countries. The reason is that high human capital countries have a comparative advantage at producing high quality goods, but are also rich enough to want to consume high quality. As a result,...

A country's most talented people typically organize production by others, so they can spread their ability advantage over a larger scale. When they start firms, they innovate and foster growth, but when they become rent seekers, they only redistribute wealth and reduce growth. Occupational...

A simple supply and demand framework is used to analyze changes in the U.S. wage structure from 1963 to 1987. Rapid secular growth in the demand for more-educated workers, 'more-skilled' workers, and females appears to be the driving force behind observed changes in the wage structure. Measured...

Medical care at the end of life, which is often is estimated to contribute up to a quarter of US health care spending, often encounters skepticism from payers and policy makers who question its high cost and often minimal health benefits. It seems generally agreed upon that medical resources are...