Neighborhoods are the key analytical unit of cities, and while neighborhoods change over time, the lines used to study them generally do not. Standard units (tracts, wards, community areas) stabilize analysis and administration, but implicitly conflate analytical or administrative convenience with the structuring forces of the city. Material urban form tells a different story. Street networks, plot arrangements, enclosure patterns, and building configurations cohere into a durable (though mutable) urban morphology that sorts accessibility, capital flows, and opportunity.
The defining features of urban form (edges, corridors, districts, etc.) often align with social, political, and economic divergence, but the correspondence is uneven because state policy and capital continually intervene at specific places and times. In Samuel Stein’s conceptualization of the “real estate state,” instruments such as upzoning, planned developments, TIFs, and related “redevelopment” policies do not act evenly across the city. They concentrate where returns and political feasibility are highest, frequently following and simultaneously reshaping the structural imperatives of the built environment. The result is an urban palimpsest in which gradually changing urban form interacts with faster-moving governance and finance to produce urban change (such as gentrification) in regularized patterns.
Prior studies in urban morphometrics have shown that form correlates with gentrification in selected cases. This proposed dissertation extends that work by shifting the unit of analysis to boundary delineations themselves and by treating policy and capital as spatially selective forces acting upon (and within) those boundary delineations.
Urban research currently lacks a suitable methodology and conceptual frame to distinguish when (and to what degree) neighborhood change is organized by urban morphology and when it is produced by political-economic processes. Current neighborhood analysis treats neighborhood delineations as fixed and exogenous when they are actually dynamic interfaces through which material form and immaterial mechanisms interact to mutually constitute urban change. This dissertation proposal extends case-based morphometric findings by making boundaries the primary object of study and by modeling how urban form and the real estate state co-produce outcomes at neighborhood edges.
Two strands of scholarship anchor this project. First, work on areal delineations of urban form show that morphological clusters and edges often track demographic and socioeconomic differences, but the strength of the relationship varies by context and is clearest when units align with morphology and edges are measured explicitly. Second, the fringe-belt tradition explains why some edges endure: growth pauses at the urban edge produce fringe belts along “fixation lines” that accumulate morphologically distinct elements like large plots, rail/utility corridors, park systems, and institutional land. These continue to buffer and differentiate districts and, under favorable coalitions, become targets for capital circuit switching and rent gap-driven reinvestment. Together these literatures justify treating edges not as cartographic or administrative artifacts but as structural urban formations that shape (and are shaped) by flows of policy intervention and capital investment.
Empirically, this dissertation asks: how do quantitative measures of urban form in Chicago – operationalized via Fleischmann et al.’s Hierarchical Morphotope Classification (HiMoC) – delineate neighborhood boundaries, and what do the resultant boundary patterns reveal about the relationship between morphology, neighborhood stability/change, and political–economic processes?
The study proceeds in three steps. The first compares HiMoC-derived boundaries with administrative and conceptual areal units to test whether built form provides a more accurate basis for analyzing change and to limit the Modifiable Areal Unit Problem (MAUP) through a foundation in urban morphology. The second evaluates correspondence by testing whether minimally aggregated socioeconomic indicators align more clearly within HiMoC boundaries than within administrative units, clarifying when patterns follow morphological boundaries versus cutting across them. The third interprets the preceding outcomes to identify when the built environment structures trajectories and when state policy and capital—Stein's “real estate state”—reinforce, redirect, or erode them.
The expected contributions of this project are also threefold. Conceptually, the project integrates urban morphometrics with political economy to show how historically constituted areal delineations (and their edges) condition the reach and efficacy of real estate state policy instruments. In doing so, it updates fringe-belt theory by specifying how major infrastructure siting and past development cycles structure contemporary intervention, and by operationalizing the resultant inherited form as measurable, citywide edges on which policy and capital selectively reinforce, redirect, or erode the inherited boundaries. Empirically, it distinguishes where neighborhood change in Chicago is driven by the structure of urban form vs. state policy and its related coalitions. Thus, it identifies corridors where the state policy/capital nexus traverses or reinforces existing physical structure. Methodologically, it advances a boundary analysis framework (combining morphology-aligned units, edge detection, and multi-scale sensitivity tests) with explicit MAUP controls, yielding an approach that will be scalable spatially, contextually, and temporally.
The result will be a clearer account of why some boundaries persist as “fault lines” while others blend or shift under spatially selective state action and a set of tools to measure boundary agreement, edge effects, and aggregation bias.