ABSTRACT
Although the census place data provide a finer-grained grid than the county-level data, they are still aggregated. The entire city of Baltimore, for example, is identified in our cluster grouping classification as Underclass while the whole of Washington, D.C., is classified as Immigrant Gateway. Both are large cities with substantial neighborhood variations that transcend the singular identity of this place data analysis. There is a scale below census places, the census tract, that provides an even finer-grained net to identify different places within Megalopolis. These tracts are the basic collection unit used by the U.S. Census Bureau. They are small, with populations ranging from 1,200 to 6,000, and are drawn so that they are the nearest statistical unit to what is commonly referred to as local neighborhood. In this chapter I will use census tracts to provide closeups of places within the large cities and illuminate the more important sources of urban change and stability. I have chosen 10 census tracts, 3 each in Boston and Washington and 4 in Baltimore, that provide a rich contrast in urban neighborhoods across Megalopolis. The simple statistics provided in Table 9-1 reveal very different urban worlds.
