Abstract - The containerized maritime transportation industry is characterized by oligopolistic
competition and economies of scale. In this paper, we examine the effect that these industry characteristics have on trade. We build a model of endogenous transportation costs within a standard Melitz (2003) framework. Countries with large trade volumes face lower transportation costs because they can take advantage of economies of scale and competition in the transportation industry. We assemble a unique dataset on the containerized maritime transportation industry. The dataset includes the freight prices for transporting a container to a foreign port, the number of transportation firms operating between the US and foreign port, and the port-to-port trade flows. We document facts that are consistent with our theory. First, countries with larger trade volumes pay less in transportation costs. Second, countries with larger trade volumes have more and larger transportation firms. We then calibrate our model and estimate a transportation technology to evaluate trade reforms. Our results indicate that transportation costs fall more in smaller markets from tariff reductions. A model that considers the endogenous response of transportation costs to a trade liberalization can generate welfare gains that are 50% more than a model in which transportation costs are constant.  

Abstract - What are the economic channels through which transportation infrastructure affect income?  We study this question using a model of internal trade in which states trade with each
other. In contrast to the previous literature, we do so in a framework that incorporates pro-competitive gains: changes in transportation costs affect the distribution of markups by affecting the level of competition that firms face. We apply this model to the case of the Golden Quadrilateral (GQ), a large road infrastructure project in India. We discipline the parameters of the model using micro level manufacturing and geospatial data. We find that: i) the project generates large aggregate gains, ii) both standard and pro-competitive gains are quantitatively relevant.


Abstract - This paper studies the interaction between financial frictions and entry barriers on growth. We construct a model in which aggregate growth is driven by the continual entry of new firms that face barriers to entry and financial frictions.  We find that reforms to financial frictions and entry barriers are substitutes—once a country has enacted one type of reform, the percentage increase in GDP from the other reform decreases.  We also show that economies with more severe financial frictions and entry costs have lower levels of output along the balanced growth path, even though all economies grow at the same constant rate. The model generates sharp predictions regarding the rate of firm creation, aggregate output levels, and aggregate growth rates, which are borne out in the cross country data.

  • "Firm Entry, Exit and Aggregate Growthwith Sewon Hur, Timothy J. Kehoe, and Kim J. Ruhl.