Quantifying Urban Diversity: Multiple Spatial Measures of Physical, Social, and Economic Characteristics - Computational Approaches for Urban Environments - page 174

An effort along these exact lines is currently being undertaken in the Crystal City
section of Arlington County, just outside of Washington, D.C. This area consists of
numerous superblocks and the county has included the addition of new cross-streets
to break up these blocks as a part of its transportation plans for this highly urbanized
area as it undergoes redevelopment. In a similar vein, using a combination of the
mixed-use parameter and UL index, city planners may identify large areas with a
poor mix of uses. This may lead to a reevaluation of zoning policies within the
city, in order to encourage a healthier mix of uses at a fine-grained level. However,
as noted by Hirt ( 2007 ), even the current efforts to modify US zoning laws fall
short of what European communities have achieved with their zoning laws. The use
of the methods presented here may open up new ideas regarding zoning laws that
encourage a more effective mix of uses under all conditions.
Based on the cluster analysis presented in the results section, it is clear that
all of the parameters as well as the UL index exhibit clustering at both ends
of the spectrum. While cause and effect is difficult to determine, it is possible
that this clustering is an effect of spillover from successful neighborhoods. As a
particular location becomes more desirable, those individuals and families who
wish to live there, but may not have the resources, may be attracted to the edges
of that neighborhood and over time begin to emulate the successes of the desired
neighborhood within their own. If this is true, it may be possible for city planners
to “seed” a neighborhood by focusing on creating a highly livable location that may
then influence the surrounding areas over time. Obviously, this is a process that can
take decades, so it is difficult to gage the effectiveness of this strategy in the short
term. It is also important to note, however, that Jacobs' ideas about livability do
not necessarily mirror that of the entire population. Thus, it becomes important to
retain areas that are well suited to all segments of a city's population. There are
some individuals that are willing to sacrifice the convenience of nearby commerce
and entertainment for the urban retreat offered by a single-family home.
While the methods presented here are structured in a manner that allows them to
be applied across a number of cities, it is important to remember the unique nature
of individual cities. As these methods are applied to other cities, researchers may
choose to strengthen the methodology by taking into consideration the unique nature
of the subject city and the data that may be available. For example, the Washington,
D.C., case study could be strengthened by dealing more effectively with the unique
presence of the Federal government within the city. The city contains an inordinately
high percentage of federally owned land that is not subject to the ordinances of
the local government; indeed Congress may overrule decisions made by the city
council. In order to account for this, it may be more useful to exclude all federal
properties and land area from the analysis or place a negative value on these
particular locations. Similarly, in a city with a significant number of waterways or
parkland, these areas may be excluded or treated in a different manner in order
to strengthen the results of the analysis. However, it was not the purpose of this
research to provide a study strictly of one city, but to provide a framework that can
be extended to other cities.