The gravity equation in international trade is one of the most robust empirical finding in economics: bilateral trade between two countries is proportional to size, measured by GDP, and inversely proportional to the geographic distance between them. While the role of size is well understood, the...

I build a model of international trade with liquidity constraints. If firms must pay some entry cost in order to access foreign markets, and if they face liquidity constraints to finance these costs, only those firms that have sufficient liquidity are able to export. A set of firms could...

We show a causal impact of immigration on innovation and dynamism in US counties. To identify the causal impact of immigration, we use 130 years of detailed data on migrations from foreign countries to US counties to isolate quasi-random variation in the ancestry composition of US counties that...

We study how decades-long exposure to individuals of a given foreign descent shapes natives' attitudes and behavior toward that group, exploiting plausibly exogenous shocks to the ancestral composition of US counties. We combine several existing large-scale surveys, cross-county data on implicit...

What is the impact of real estate prices on corporate investment? In the presence of financing frictions, firms use pledgeable assets as collateral to finance new projects. Through this collateral channel, shocks to the value of real estate can have a large impact on aggregate investment. Over...

We analyze a large dataset of commercial records produced by Assyrian merchants in the 19th Century BCE. Using the information collected from these records, we estimate a structural gravity model of long-distance trade in the Bronze Age. We use our structural gravity model to locate lost ancient...

We use 130 years of data on historical migrations to the United States to show a causal effect of the ancestry composition of US counties on foreign direct investment (FDI) sent and received by local firms. To isolate the causal effect of ancestry on FDI, we build a simple reduced-form model of...

We explore the mechanics of empathy. In a controlled immersive virtual reality experiment, we show that neutral information on unauthorized immigration magnifies the empathetic response of subjects when they witness the struggles of unauthorized migrants. We conjecture that perceiving others as...

We generalize Krugman's (1979) 'new trade' model by allowing for an explicit production chain in which a range of tasks is performed sequentially by a number of specialized teams. We demonstrate that an increase in market size induces a deeper division of labor among these teams which leads to...