We develop a model where the unemployed workers in the city can find a job either directly or through weak or strong ties. We show that, in denser areas, individuals choose to interact with more people and meet more random encounters (weak ties) than in sparsely populated areas. We also...

The world is replete with spatial frictions. Shipping goods across cities entails trade frictions. Commuting within cities causes urban frictions. How important are these frictions in shaping the spatial economy? We develop and quantify a novel framework to address this question at three...

We develop a new general equilibrium model of trade with heterogeneous firms, variable demand elasticities and endogenously determined wages. Trade integration favors wage convergence, intensifies competition, and forces the least efficient firms to leave the market, thereby affecting aggregate...