Quantifying Urban Diversity: Multiple Spatial Measures of Physical, Social, and Economic Characteristics - Computational Approaches for Urban Environments - page 148

reverse of the New Urbanists, stating that, “to be sure, a good city neighborhood can
absorb newcomers into itself, both newcomers by choice and immigrants settling
by expediency, and it can protect a reasonable amount of transient population
too” ( 1992 , pp. 137-138). Here, Jacobs sees the diversity as inherent in the good
neighborhood, with the ability to adapt and absorb, as opposed to a diversity that
needs to be created. To be fair, she also indicates that diversity is not inherent and
thus proposes the four characteristics that she sees as necessary for the creation and
sustainability of diversity. In the chapter entitled “Gradual money and cataclysmic
money,” she warns against sudden infusions of money that “[pour] into an area in
concentrated form, producing drastic changes” (Jacobs 1992 , p. 293) which may
produce challenges because, according to Jacobs, “All city building that retains
staying power after its novelty has gone and that preserves the freedom of the
streets and upholds citizens' self-management, requires that its locality be able to
adapt, keep up to date, keep interesting, keep convenient, and this in turn requires a
myriad of gradual, constant, close-grained changes” ( 1992 , p. 294). The distinctions
between Jacobs' original work and its incorporation into the New Urbanism
movement are important, since much existing research and critique has focused on
the principles of the New Urbanists, rather than the original ideas of Jacobs.
Many of the critics of Jacobs and the New Urbanist ideals focus on evaluating
them from a single perspective, such as traffic reduction. The research of Filion
and Hammond ( 2003 ) is an excellent example. The authors question the wisdom
of neo-traditional (i.e., New Urbanism) design, noting that they do not “necessarily
enhance pedestrian accessibility rates” and “are not as effective at diverting through
traffic away from residential streets as those of newer neighborhoods” (Filion and
Hammond 2003 ). Jacobs would likely take this statement as an example of a focus
on segregating uses (residential streets versus commercial corridors) and travel
modes. Jacobs herself did not see automobiles as an enemy; “we blame automobiles
for too much” ( 1992 , p. 338). Instead, she views automobile use as a necessary,
though over-used, means of transport - and as especially critical for conducting
commerce. “To concentrate on riddance as the primary purpose, negatively to put
taboos and penalties on automobiles as children might say, 'Cars, cars go away,'
would be a policy not only doomed to defeat but rightly doomed to defeat” (Jacobs
1992 , p. 360). The conclusions of Filion and Hammond are likely due to their
decision to approach the research from a perspective that differs from Jacobs' with
regard to the separation of travel modes and uses.
Similarly, much of the research into Jacobs' four generators of diversity has
focused on only one or two of the generators in isolation. A number of studies
have been conducted into the effects of mixed-use development. Grant ( 2002 ) found
that “mixed use districts are becoming more segregated by class, and affordability
has not improved. Efforts to mix uses have not stanched the loss of economic
vitality for most Canadian cities.” However, this research focused on mixed use in
the suburban context, a location where Jacobs (as noted earlier) had no intention
of her ideas being utilized. Some research has focused on the level of physical
deterioration of structures (as a proxy for the success or failure of the community)
within a mixed-use context, finding that there are increased levels of deterioration