We estimate the demand for a videocalling technology in the presence of both network effects and heterogeneity. Using a unique dataset from a large multinational firm, we pose and estimate a fully dynamic model of technology adoption. We propose a novel identification strategy based on...

Much debate exists around the impact that illegal file sharing may have on the creative industries. Similarly, opinions differ regarding whether the producers of artistic works should be forced to accept any weakening of intellectual property rights resulting from illegal file sharing, or if...

We introduce a new measure of social connectedness between U.S. county-pairs, as well as between U.S. counties and foreign countries. Our measure, which we call the "Social Connectedness Index" (SCI), is based on the number of friendship links on Facebook, the world's largest online social...

We use anonymized data from Facebook to construct a new measure of the pairwise social connectedness between 180 countries and 332 European regions. We find that two countries trade more with each other when they are more socially connected and when they share social connections with a similar...

We report a puzzling pair of facts concerning the organization of science. The concentration of research output is declining at the department level but increasing at the individual level. For example, in evolutionary biology, over the period 1980 to 2000, the fraction of citation-weighted...

We discuss self-interested uses of equity arguments in international climate negotiations. Using unique data from a world-wide survey of agents involved in international climate policy, we show that the perceived support of different equity rules by countries or groups of countries may be...

We use a novel dataset of online prices of identical goods sold by four large global retailers in dozens of countries to study good-level real exchange rates and their aggregated behavior. First, in contrast to the prior literature, we demonstrate that the law of one price holds very well within...