We examine how the spatial and social proximity of inventors affects knowledge flows, focusing especially on how the two forms of proximity interact. We develop a knowledge flow production function (KFPF) as a flexible tool for modeling access to knowledge and show that the optimal spatial...

Building on standard marital matching models, we show that a variety of underlying social preferences about a given trait all generate positive assortative matching on that trait, and hence the same distribution of spousal trait differences in equilibrium. Applying this result to U.S. Census and...

Does the lack of peers contribute to the observed gender gap in entrepreneurial success, and is the constraint stronger for women facing more restrictive social norms? We offered two days of business counseling to a random sample of customers of India's largest women's bank. A random subsample...

We find that a firm's investment is highly sensitive to the investments of other firms headquartered nearby, even those in very different industries. It also responds to fluctuations in the cash flows and stock prices (q) of local firms outside its sector. These patterns do not appear to reflect...

We study the distribution of economic activity, as proxied by lights at night, across 250,000 grid cells of average area 560 square kilometers. We first document that nearly half of the variation can be explained by a parsimonious set of physical geography attributes. A full set of country...

Based on recent theoretical developments I argue that the average level of human capital is a local public good. Cities with higher average levels of human capital should therefore have higher wages and higher land rents. After conditioning on the characteristics of individual workers and...

Alfred Marshall argues that industrial agglomerations exist in part because individuals can" learn skills from each other when they live and work in close proximity to one another. An" increasing amount of evidence suggests that the informational role of cities is a primary reason for" their...

The degree of geographic concentration of individual manufacturing industries in the U.S. has declined only slightly in the last twenty years. At the same time, new plant births, plant expansions, contractions and closures have shifted large quantities of employment across plants, firms, and...

Faster technological progress has long been considered a key potential benefit of agglomeration. Physical proximity to others may help inventors adopt new ideas in their work by increasing awareness about which new ideas exist and by enhancing understanding of the properties and usefulness of...

We study resource allocation within households in Côte d'Ivoire. In Côte d'Ivoire, as in much of Africa, husbands and wives farm separate plots, and there is some specialization by gender in the crops that are grown. These different crops are differentially sensitive to particular kinds of...