Firms are more productive on average in larger cities. Two main explanations have been offered: firm selection (larger cities toughen competition, allowing only the most productive to survive) and agglomeration economies (larger cities promote interactions that increase productivity), possibly...

We develop a new methodology to estimate the elasticity of urban costs with respect to city population using French land price data. Our preferred estimate, which handles a number of estimation concerns, stands at 0.041. Our approach also yields a number of intermediate outputs of independent...

We propose an integrated framework to discuss the empirical literature on the local determinants of agglomeration effects. We start by presenting the theoretical mechanisms that ground individual and aggregate empirical specifications. We gradually introduce static effects, dynamic effects, and...