The effects of ethnic geography, i.e., the distribution of ethnic groups across space, on economic, political and social outcomes are not well understood. We develop a novel index of ethnic segregation that takes both ethnic and spatial distances between individuals into account. Importantly, we...

This paper studies the social and economic responses to the Covid-19 pandemic in a large sample of countries. I stress, in particular, the importance of countries' interconnections to un-derstand the spread of the virus. I estimate a Global VAR model and exploit a dataset on existing social...

We study a model of social learning in networks where the dynamics of beliefs are driven by conversations of dissonance-minimizing agents. Given their current beliefs, agents make statements, tune them to the statements of their associates, and then revise their beliefs. We characterize the...

Traditional economic theory of collusion assumed that cartels are inherently unstable, and yet some manage to operate for years or even decades. While the literature has presented several determinants of cartel stability, the vast majority focuses on firms as entities, even though cartels are...

We examine friendships and study partnerships among university students over several years. At the aggregate level, connections increase over time, but homophily on gender and ethnicity is relatively constant across time, university residences, and different network layers. At the individual...

How do political preferences and voting behaviors respond to information coming from abroad? Focusing on the international migration network, I document that opinion changes at the origins spill over to 1st- and 2nd-generation immigrants abroad. Local diasporas, social media, and family ties to...

We study how social interaction and friendship shape students' political opinions in a natural experiment at Sciences Po, the cradle of top French politicians. Quasi-random assignments of students into the same short-term integration groups before their scholar curriculum reduce political...

Migration contributes to the circulation of goods, knowledge, and ideas. Using community and individual-level data from Moldova, we show that the emigration episode that started in the late 1990s strongly affected political preferences and electoral outcomes in Moldova during the following...

We document the spatial diffusion of Friedrich Froebel’s radical invention of kindergartens in 19th-century Germany. The first kindergarten was founded at Froebel’s birthplace. Early spatial diffusion can be explained by cultural proximity, measured by historical dialect similarity, to...