Economies of Transport Density and Industrial Agglomeration

This paper develops a model of a spatial economy in which interregional trade patterns and the structure of the transport network are determined endogenously as a result of the interaction between industrial location behavior and increasing returns in transportation, in particular, economies of transport density. The traditional models assume either the structure of the transport network or industrial location patterns, and hence, they are unable to explain the interdependence of the two. It is shown that economies of transport density can be the primary source of industrial localization.

Bounding ATE with ITT

We propose the bounds on ATE using intention-to-treat (ITT) estimator when there are compliers/noncompliers in randomized trials. The bounds are given as ITTge treatment effect (CACE) can be computed from ITT and complier ratio. We show that these bounds can be derived from two assumptions: (1) average treatment effect is greater with compliers than noncompliers or CACE>NACE, (2) noncompliers' average treatment effect (NACE) is nonnegative. We give an example of poverty impacts of health insurance, and effects of adverse selection and moral hazard of health insurance.