This PDF is a selection from a published volume …（这个PDF是一个选择从出版卷u2026）.pdf

This PDF is a selection from a published volume from the National Bureau of Economic Research Volume Title: Agglomeration Economics Volume Author/Editor: Edward L. Glaeser, editor Volume Publisher: The University of Chicago Press Volume ISBN: 0-226-29789-6 Volume URL: /books/glae08-1 Conference Dates: November 30-December 1, 2007 Publication Date: February 2010 Chapter Title: Introduction Chapter Author: Edward L. Glaeser Chapter URL: /chapters/c7977 Chapter pages in book: (1 - 14) Introduction Edward L. Glaeser Agglomeration economies are the benefi ts that come when fi rms and people locate near one another together in cities and industrial clusters. These ben- efi ts all ultimately come from transport costs savings: the only real difference between a nearby fi rm and one across the continent is that it is easier to con- nect with a neighbor. Of course, transportation costs must be interpreted broadly, and they include the difficulties in exchanging goods, people, and ideas. The connection between agglomeration economies and transport costs would seem to suggest that agglomerations should become less impor- tant, as transportation and communication costs have fallen. Yet, a cen- tral paradox of our time is that in cities, industrial agglomerations remain remarkably vital, despite ever easier movement of goods and knowledge across space. Declining transport costs have facilitated trade between China, India, and the rest of the world, but within those countries, development has centered in urban areas. Across the world, urbanization continues to increase, and the United Nations reports that by the end of 2008, one- half of the world will live in cities.1 Indeed, megacities have become the gateways between those developing countries and the developed world. Within the richer nations of the West, many cities, like New York and London, have experienced remark- able comebacks since the dire da