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...

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...

Economic societies emerged during the late eighteenth-century. We argue that these institutions reduced the costs of accessing useful knowledge by adopting, producing, and diffusing new ideas. Combining location information for the universe of 3,300 members across active economic societies in...

The diffusion of knowledge in the world generates positive externalities if knowledge flows increase the productivity of R&D. Our work analyzes knowledge diffusion and knowledge externalities in generating innovation and in determining productivity. We first estimate the determinants of...

This paper presents a study of backward and forward patent citations in patents granted to firms and institutions in the Netherlands by the United States Patent and Trademark Office (USPTO). The study establishes different patterns of patent citation in recent Dutch patents belonging to...

Two innovations in the last century have changed dramatically the cost of communicating and transmitting information: The first is the widespread adoption of telephony; the second is the internet. We study the implications of these changes in ICT for urban structure. We find robust evidence that...