Combes, Pierre‐Philippe, et al. "The productivity advantages of large cities: Distinguishing agglomeration from firm selection." Econometrica 80.6 (2012): 2543-2594.
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 reinforced by localized natural advantage. To distinguish between them, we nest a generalized version of a tractable ﬁrm selection model and a standard model of agglomeration. Stronger selection in larger cities lefttruncates the productivity distribution, whereas stronger agglomeration right-shifts and dilates the distribution. Using this prediction, French establishment-level data, and a new quantile approach, we show that ﬁrm selection cannot explain spatial productivity differences. This result holds across sectors, city size thresholds, establishment samples,and area deﬁnitions.
É o paper empírico mais barra pesada Nova Geografia Econômica que eu já vi. Impressionante.