Doctoral Dissertation Research in Economics: Urban Transit Infrastructure and the Growth of Cities

本项目研究城市交通基础设施的提供如何影响城市内的增长和房地产价值。量化交通项目对城市发展和房地产价值的影响被证明是困难的，原因至少有两个。首先，交通基础设施可能会带来增长和房地产价值的上升，但后者也可能导致交通项目。其次，一些规模最大、最有趣的交通项目早在计算机出现之前就开始了，因此相关数据被锁在不同的纸质记录中。为了解决这些问题，研究者在介绍纽约市公共交通基础设施的过程中利用了一个独特的历史背景，并进一步创建了机器可读形式不存在的新数据集。这些新数据集提供了非常高的地理分辨率，并能够以同样高的分辨率研究城市内部的空间经济相互作用。这个广泛的数据库有助于揭示随着交通基础设施的发展，城市空间发展的演变。该项目开发了一个结构模型，描述了城市内交通网络的扩张和经济活动的相关重组。为了实现这一目标，研究者(1)构建了一个综合空间框架，明确地模拟了交通冲击对家庭和企业区位选择的影响；(2)将19世纪末和20世纪的纽约市及其周边地区数字化并创建了一个新的数据集；(3)将数据带入模型，应用框架测度城市交通基础设施的影响；(4)开发一种识别策略，使估计的影响具有因果解释。该项目提供了一个综合框架，可适用于存在空间联系的许多领域，有助于将贸易、经济地理学和城市经济学领域整合在一个统一的框架中。从这一建议中开发的结果和工具可以很容易地纳入其他情况，从而实现更有理论基础的实证分析。利用这种结构估计方法，研究人员可以进行回顾性和前瞻性的政策分析。最后，从这个项目中创建的数据库可以让研究人员在多个空间联系的存在下研究复杂的一般平衡效应。

This project investigates how the provision of urban transportation infrastructure affect growth within cities and property values. Quantifying the effect of transportation projects on city growth and property values has proven difficult for at least two reasons. First, transportation infrastructure may produce growth and a rise in property values, but the latter may also lead to transportation projects. Second, some of the largest and most interesting transportation projects were undertaken long before the advent of computers, so that the associated data has been locked up in disparate paper records. To address these issues, the investigator exploits a unique historical setting in the introduction of the mass-public transit infrastructure in New York City, and further creates novel datasets that have not existed in machine-readable form. These new datasets provide a very high level of geographic resolution and enable the study of spatial economic interactions at a similarly high level of resolution within the city. This extensive database helps shed light on the evolution of spatial development in the city as transportation infrastructure is developed. This project develops a structural model describing the expansion of the transit network and associated reorganization of economic activities within the city. To achieve this goal, the investigator (1) constructs an integrated spatial framework that explicitly models the impact of transit shocks on location choices of households and firms; (2) digitizes and creates a novel dataset of the late nineteenth and twentieth century New York City and its surrounding areas; (3) takes the data to the model and applies the framework to measure the impact of urban transit infrastructure; (4) develops an identification strategy that allows the estimated impacts to have a causal interpretation. This project provides an integrated framework that can be applicable to many fields where spatial linkages are present, contributing to integrate the fields of trade, economic geography, and urban economics in a unified framework. Results and tools developed from this proposal can be readily incorporated to other circumstances, enabling more theoretically-grounded empirical analyses. Using this structural estimation approach, researchers can conduct both retrospective and prospective policy analysis. Finally, the database created from this project can allow researchers to investigate complex general equilibrium effects in the presence of multiple spatial linkages.