Simple Agents, Complex Emergent City: Agent-Based Modeling of Intraurban Migration - Computational Approaches for Urban Environments - page 121

6.2 Conceptual Model of Intraurban Migration

A core conceptual challenge in understanding intraurban migration is developing
theories of how individual behavior leads to complex urban patterns and processes.
Intraurban migration has three interrelated components, as introduced by Wolpert
( 1965 ) and expanded over the years: (1) housing conditions, or the broad social,
demographic, economic, and environmental conditions that trigger household mi-
gration; (2) housing utilities, expressed as the balance between utilities of the current
housing and expected utilities of other housing opportunities; and (3) housing
search, or the search process and perceptions of housing by potential buyers.
Intraurban migration research focuses primarily on the first and second components,
while a smaller body of work centers on the third component of housing search as a
sociospatial process that guides the first and second.
We advance this third component by testing a modified intervening opportunity
theory, drawing on sociospatial conceptions of housing perception to examine
simple decision-making rules that lead to realistic complex migration patterns in
aggregate. This third component helps guide the first two and can be examined
separately, which does not minimize the fact that the residential choices of house-
holds are driven in part by a host of demographic and socioeconomic characteristics
of migrants combined with housing utilities, including housing structure, the
biophysical environment, neighborhood quality, as well as accessibility to services
(Adams 1984 ; Quigley and Weinberg 1977 ;Clark 2008 ). Additional considera-
tions include household factors ranging from income and race to environmental
preferences (Choldin 1973 ; Pellegrini and Fotheringham 2002 ; Jones et al. 2004 ).
These factors in turn modify the effect of housing conditions and their attendant
perceived difference in utilities (De Jong and Roempke Graefe 2008 ; Geist and
McManus 2008 ; Mulder 2007 ; Cooke 2008 ), interactions with commuting and
transportation infrastructure (Clark, Huang, and Withers 2003 ; Rouwendal and
Rietveld 1994 ), government policies and developer decisions (Brown and Chung
2008 ), and the lending practices of financial institutions (Brown and Longbrake
1970 ; Brown and Moore 1970 ;Clark 1982 ). In sum, a wide variety of factors
influence housing conditions and housing utilities and, by extension, intraurban
migration and urbanization more generally.
Despite the importance of housing conditions and housing utilities, the third
component of housing search and perception has much to do with the nature of
intraurban migration because it guides the effects of the first two components. This
component has a distinguished research history, but overall it has received far less
attention than the first two components. Theories of housing search complement
our understanding of these other components because they posit that there are
fundamental regularities in how households perceive housing opportunities. Much
of this research emphasizes the distinct spatial and temporal limits of homebuyers'
search strategies in local and regional housing markets (Clark 1982 ;Clarkand
Flowerdew 1982 ; Smith et al. 1979 ). Related work examines how home search and
job search interact, particularly in how people think about where they want to live
as a function of where they want to work (Waddell 1993 ; van Ommeren et al. 1997 ;