Recovery of causal relationships in data is an essential part of scholarly inquiry in the social sciences. This chapter discusses strategies that have been successfully used in urban and regional economics for recovering such causal relationships. Essential to any successful empirical inquiry is...

Any interesting model of economic geography must involve a tension between "centripetal" forces that tend to produce agglomerations and "centrifugal" forces that tend to pull them apart. This paper explores one such model, and shows that the model links together a number of themes in the...

The theoretical framework of urban and regional economics is built on transportation costs for manufactured goods. But over the twentieth century, the costs of moving these goods have declined by over 90% in real terms, and there is little reason to doubt that this decline will continue....

This article describes methods used in the field of spatial economics that combine insights from economic theory and evidence from data in order to answer counter- factual questions. I outline a general framework that emphasizes three elements: a specific question to be answered, a set of...

An important element of the cost of distance is time taken in delivering final and intermediate goods. We argue that time costs are qualitatively different from direct monetary costs such as freight charges. The difference arises because of uncertainty. Unsynchronised deliveries can disrupt...

The new' economic geography focuses on the footloose-labor and the vertically-linked-industries models. Both are complex since they feature demand-linked and cost-linked agglomeration forces. I present a simpler model where agglomeration stems from demand-linked forces arising from endogenous...

In applied historical research, geographic units often differ in level of aggregation across datasets. One solution is to use crosswalks that associate factors located within one geographic unit to another, based on their relative areas. We develop an alternative approach based on relative...

This paper studies the role of technology in local-government tax collection capacity in the developing world. We first conduct a new census of all local governments in Ghana to document a strong association between technology use and property tax billing, collection and enforcement. We then...