Fall 2009-Summer 2012
The use of geodemographic data is common in the regulation of urbanized land and development. Demand for geodemographics has created an industry of commercial providers retailing complex data assemblages, called market segmentation sets, describing synthetic consumer identity groups and linking these groups to their locations in urbanized space through GIS. Among other uses, this data directs real estate development. Radical Railbanking articulates a position from which architects may find agency within the hegemony of geodemographics.
Over the past several decades, the use of geodemographic data has grown ubiquitous in the regulation of urban land use and development. City planning commissions use geodemography to aid in the implementation of policy, and private corporations reference geodemographic data when purchasing, selling or developing real-estate. Demand for geodemographics has created a surging industry of providers, such as Claritas and Axciom, that collate and retail data for commercial use. These corporations collect census data, consumer spending statistics, figures scraped from internet usage, and information about race, ethnicity, sexuality, income and consumer tastes. These statistics are then amalgamated into data called market segmentation sets, which describe idiosyncratic and highly synthesized consumer identities and link these identities to their spatial locations in our cities or urbanized areas. These data sets, and their instrumentalization through GIS, attempt to make the distribution of identity across geographic space scientifically knowable. In doing so, these practices impose a narrow epistemological regime – privileging extant quantitative variation over latent qualitative difference and accepting as scientific fact distinctions about race, gender and ethnicity that are merely naturalized. For these reasons, among others, market segmentation geodemography is often assailed as statistically unfounded, and ideologically contentious.
Nevertheless, market segmentation sets are increasingly used to guide commercial urban development. Thus, the built environment plays a critical role in their instrumentalization. When real-estate companies use market segmentation data to choose a site for development, the resultant buildings deeply implicate the synthetic identities targeted. The presence of the shopping malls, big-box outlets or fields of coffee houses that result encourages the predicted consumer behavior. These entities become territorial beacons for the collection of a specific combination of consumers. United in space, this combination of consumers – in effect – becomes the synthesized consumer identity described in the operative geodemography. In this way, development guided by market segmentation geodemographics forges a complexly solipsistic relationship between constructed consumer identity, and the construction of the built environment. These practices serve to reify artificial sociocultural divisions based on the categories of data collection and limit potential urban development to the repetition of conventional consumer building formats. Thus, while some have argued against the validity of market segmentation data, and this data’s underlying demographic distinctions are constructed, the development guided by market segmentation geodemography serves to make its assumptions real. These data sets re-describe the spatiality of our cities as an assemblage of spatio-statistical territories populated by hybridized consumer identities.
Figure 1: Aerial of Detroit with selected railways in pink
Territories lining the railways in Detroit
Railbanking is a process through which unused railways and easements may be turned over for development as public space. Historically, railways have been assembled from land parcels with varied and discrete ownership types. Some parcels are owned out-right by rail companies, while others are regulated by complex ownership agreements, limited rights of use or temporary government land grants. When a rail company abandons a railway, property rights for the land parcels composing the rail default to differing beneficiaries depending on their original ownership type. Railbanking provides an omnibus legal proceeding through which the complex patterns of ownership around an unused railway may be consolidated and a new public realm may emerge.
This project hijacks and radicalizes the tactics of railbanking by manipulating geodemography through the productive misuse of conventional GIS software. In doing so, the project attempts to locate a constructive position relative to the hegemony of market segmentation geodemography from which the architect can operate. The project’s site encompasses several lengths of active railway in Detroit that currently negotiate abrupt formal and demographic division. (Figure 1) Just as conventional railbanking uses a legal proceeding to consolidate land rights in yield of public space, Radical Railbanking uses GIS to analyze and recombine development potentials that are latent in the spatial and statistical relationships between the land parcels along Detroit’s rails. The process makes visible potentials for urban development that would not register within the episteme of conventionally applied geodemography.
Key to the Radical Railbanking process is a modeling technique called TIN modeling. Common to many GIS platforms, TIN is an acronym for Triangular Interpolated Network. TINs are typically used in GIS to model topography and enable subsequent ecological analyses. But Radical Railbanking misuses TIN models to eschew and hybridize the categories of conventional geodemography. Thus, while most applications of GIS are fundamentally positivist and limited by the categories of data collection within their applied geodemography, this project is fundamentally relational, spatially and statistically reformulating data.
An initial TIN model is created by offsetting the profile of the selected railways one half mile to each if its sides and interpolating population density values as they register at the offset lines across the resultant corridor. (Figure 2) This interpolation creates a model with an abruptly serrated profile, imaging differing intensities in population density in relation to the geometric offset of the selected railways. Thus, statistical certainty is reformulated as a spatial and statistical relationship. The serrated model is analyzed and the ridges with the highest values are isolated. These ridges indicate relatively high population density values where they intersect with either one, or both, railway-offset lines. Lines at the locations of these ridges are projected back onto the city and combined with the railways to create a “Connective Armature Diagram” across the railway’s dormant proximity. This is a projective diagram for new development along the railway that, critically, is based on a fundamental reformulation of conventional geodemography. The diagram is meant to locate trajectories for development that might stitch together unusually vital neighborhoods, channel one zone of higher density into another of lower density, and organize the aggregation of further spatio-statistical relationships in a second round of analysis.
The geometry of the Connective Armature Diagram is then used as a basis for a series of second-generation TINs. (Figure 3) Datasets for these TINs are chosen for one of two reasons. The first category of data sets relate to conventional demographic categories that seek to define a “community” such as the African American “community” or the Hispanic “community.” Under this category, demographics are used for the total African American, Hispanic, Caucasian, and Youth populations. The second category of data sets are chosen because they relate to programs that have been historically conceptualized as structural elements within urbanism, such as schools, churches or transit stations. Under this category, demographic figures such as the Blue-Collar Worker Population, the Highly Educated Population, the Religion Index and Mass Transit Ridership are used. This step in the Radical Railbanking process images relationships between data values as they register on the Connective Armature Diagram, and projects those relationships across the space between. Hence, standard geodemography, with all of its positivist biases, is again reformulated and made increasingly spatially and statistically relational. No longer representing a singular statement of statistical “fact,” the second generation TINs reformulate and hybridize datasets in relation to the Connective Armature Diagram and the data used in its initial creation. The result is a set of TIN models of complex pseudo-topographic triangulation. These models are then analyzed using a standard topographic analysis function to isolate only those faces of their triangulated surfaces with the most intense slope values. (Figure 4) Under the assumption that the territories with the highest gradient of difference are those most potentially mercurial, these high-slope faces are interpreted as regions in the compound spatio-statistical relationships imaged where the values indicate volatility, or where the most possibility for change exists. In each of these steps, the intended uses of conventional GIS are co-opted, and geodemographic classifications are hybridized.
Figure 3: Second Generation TIN
Figure 4: High Slope Regions
III. Rezoning and Pattern Recognition
The high-slope regions are then projected back on to the city. The resultant drawing is conceptualized as a kind of re-imagined zoning map. Figure 5 Added to the map are fields of very low value, land banked or city owned properties. These are thought of as parcels immediately available for use in any future redevelopment strategy. Also added are schools, parks, and major roads, all of which are understood as existing entities that may inform decision making. When high slope regions from the Blue Collar Population TIN occupy available parcels, they are labeled Production Territories, hosting new factories, company towns and so on; high slopes from the Religion Index TIN create Religious Territories, hosting centers of worship, pilgrimage trails, distributed nunneries, and more; high slopes from the Highly Educated Population TIN generate Educational Territories, suggesting new vocational training facilities, magnet schools and the reuse of residential fabric as dormitories or faculty housing. Similar territorial designations are made for zones where each of the high slopes from the second generation TINs intersect available land. (See Figure 13 Legend) Within these territories, incentives are sometimes stipulated for urban programs that directly solicit a demographic or market group modeled, like a tax bonus for new green-industry development where an intense relationship between blue collar worker populations occurs. Elsewhere, in zones where several intense spatio-demographic relationships overlap, urban programs that cut-across or hybridize the conventional categories of geodemography are encouraged – like megachurches or sports complexes. These kinds of entities are labeled “Civic Infrastructures.” The Connective Armature Diagram, which is latently present as the geometric base of the spatio-demographic relationships modeled in the TINs, is concretized as incentives for the development of a continuous network of public spaces that stitches neighborhoods together. The map strategically encourages a series of contemporary “best-practice” urban programs – like urban farming and community centers – but deploys them in a way that is meant to intensify the relationship between urban programs and events, elevating latent urban volatility. The map is sometimes blatantly prescriptive, but these prescriptions are intended to be catalytic of playful and unpredictable urban development.
Most zoning maps simply segregate occupancy and regulate development density, and could thus easily sit within the positivist episteme of conventional geodemography. Counter to this, the Radical Railbanking zoning map displays a rich density of pattern reading against pattern; relationships compounding and inflecting one-another. Using the map to generate strategies for urban development requires a process of pattern recognition: deciphering, designing, and making rules for operating within the relationships that the map makes visible. Hence, the map becomes a sort of medium for the projection of architectural and urban imagination, but one that is yielded through a co-opting of techniques of scientific control. Unlike the commercial or mainstream applications of geodemography, the map never reiterates or reifies conventional or constructed identity categories. Instead, buildings and urban designs guided by the Radical Railbanking process incentivize the emergence of creative urban identities and hybrid urban collectives – describing a city that is solicitous of imaginative architectural interventions.
Figure 5: Final zoning map
Final Zoning Map enlargements