When will a monopolist have incentives to foreclose a complementary market by degrading compatibility/interoperability of his products with those of rivals? We develop a framework where leveraging extracts more rents from the monopoly market by "restoring" second degree price discrimination. In...

We model spatial clusters of similar firms. Our model highlights how agglomerative forces lead to localized, individual connections among firms, while interaction costs generate a defined distance over which attraction forces operate. Overlapping firm interactions yield agglomeration clusters...

This chapter reviews academic research on the connections between agglomeration and innovation. We first describe the conceptual distinctions between invention and innovation. We then describe how these factors are frequently measured in the data and some resulting empirical regularities....

Employment growth is strongly predicted by smaller average establishment size, both across cities and across industries within cities, but there is little consensus on why this relationship exists. Traditional economic explanations emphasize factors that reduce entry costs or raise...

Why are some places more entrepreneurial than others? We use Census Bureau data to study local determinants of manufacturing startups across cities and industries. Demographics have limited explanatory power. Overall levels of local customers and suppliers are only modestly important, but new...

Measures of entrepreneurship, such as average establishment size and the prevalence of start-ups, correlate strongly with employment growth across and within metropolitan areas, but the endogeneity of these measures bedevils interpretation. Chinitz (1961) hypothesized that coal mines near...

Economists have shown that large and persistent differences in productivity levels across businesses are ubiquitous. This finding has shaped research agendas in a number of fields, including (but not limited to) macroeconomics, industrial organization, labor, and trade. This paper surveys and...

We argue that the intrinsic inefficiency of proprietary software has historically created a space for alternative institutions that provide software as a public good. We discuss several sources of such inefficiency, focusing on one that has not been described in the literature: the...

Do national borders and ethnicity contribute to market segmentation between and within countries? This paper uses unique and high-frequency data on narrowly-defined goods to gauge the extent to which a national border impedes trade between developing countries (Niger and Nigeria). Using a...

Tenancy has been a means for labor to advance their socio-economic condition in agriculture yet in Brazil and Latin America, tenancy rates are low compared to the U.S. and the OECD countries. We test for the importance of insecure property rights in Brazil on the reluctance of landowners to rent...