Reassessing Railroads and Growth: Accounting for Transport Network Endogeneity
Motivated by the seminal work of Robert Fogel on U.S. railroads, I reformulate Fogel's original counter- factual history question on 19th century U.S. economic growth without railroads by treating the transport network as an endogenous equilibrium object. I quantify the effect of the railroad on U.S. growth from its introduction in 1830 to 1861. Specifically, I estimate the output loss in a counterfactual world with- out the technology to build railroads, but retaining the ability to construct the next-best alternative of canals. My main contribution is to endogenize the counterfactual canal network through a decentralized network formation game played by profit-maximizing transport firms. I perform a similar exercise in a world without canals. My counterfactual differs from Fogel's in three main ways: I develop a structural model of transport link costs that takes heterogeneity in geography into account to determine the cost of unobserved links, the output distribution is determined in the model as a function of transport costs, and the transport network is endogenized as a stable result of a particular network formation game. I find that railroads and canals are strategic complements, not strategic substitutes. Therefore, the output loss can be quite acute when one or the other is missing from the economy. In the set of Nash stable networks, relative to the factual world, the median value of output is 45% lower in the canals only counterfactual and 49% lower in the railroads only counterfactual. With only one of the transportation technologies available, inequality in output across cities would have been lower in variance terms but sharply higher in terms of the maximum-minimum gap. Such a stark output loss is due to two main mechanisms: inefficiency of the decentralized equilibrium due to network externalities and complementarities due to spatial heterogeneity in costs across the two transport modes.