Research


Zoning and housing regulation


My first line of research examines how zoning and the regulatory environment shape the housing supply. In one paper, I test the implicit theory underpinning upzoning using national zoning data from 2003-2019. Upzoning reforms attempt to counter restrictive zoning policies that have constrained the housing supply. I find that increasing the maximum allowable residential density in a municipality alone is not associated with significant increases in housing density. However, increases in housing density, regardless of zoning changes, are associated with a small increase in the number and share of non-Hispanic Black residents and a decrease in the share of non-Hispanic White residents. While allowing for more residential density is a necessary first step to increasing the housing supply, bundling these law changes with other policy changes that promote housing development may be more effective in increasing the housing supply.


I build on this work in a series of papers that study the relationship between rezoning initiatives and neighborhood change in New York City. In one paper, I exploit New York City’s extensive stock of rent-stabilized buildings to better understand rent changes as a mechanism contributing to increased out-migration from upzoned areas found in previous work. In other work, I examine how city-led neighborhood-level rezonings shape the housing market and distribute real estate benefits in ways that perpetuate spatial inequality. In other zoning-related work, I conduct a qualitative case study of a small town enacting a zoning law for the first time and find that spillover from the nearby city has shifted the demographics and political majority in this small town, leading to conflict between longtime landowners and newcomers over views on property rights and the town’s character.


Housing finance


My second line of research examines how housing finance affects residential segregation and mobility patterns. Affordable housing policies play a role in the reproduction of segregation, including the Low-Income Housing Tax Credit (LIHTC), which is the largest source of federal funding for the development of affordable housing in the U.S. In one paper, I ask: To what degree does LIHTC reduce racial disparities in residential attainment? I use unique residential history data from a large consumer database to compare the mobility patterns of LIHTC and private market tenants in California. I find that LIHTC tenants have lower probabilities of moving to higher resource areas than low-income private market tenants; however, these aggregated probabilities mask differences by race. Non-Hispanic White LIHTC tenants are more likely to have higher levels of residential attainment compared to non-White LIHTC tenants. 


Publications


Peer-Reviewed Journal Articles


Sullivan, Laura R. 2025. “Testing the Chain of Inclusion: Examining if Upzoning Changes the Housing Supply and Demographics of Places Using National Data.” Journal of Urban Affairs, 1-22. JUA 


Zoning policies have contributed to segregation in the U.S., and recent government initiatives have aimed to reform these policies through upzoning—increasing allowable housing density. In theory, upzoning should reduce segregation by increasing housing density, leading to greater affordability and accessibility to marginalized groups. I use zoning data from the 2003-2019 National Longitudinal Land Use Survey to test the theory underpinning the process of upzoning, asking: (1) Does upzoning increase housing density? (2) Does an increase in housing density change the demographics of a place? I find that increasing the maximum allowable residential density in a municipality alone is not associated with significant increases in housing density. However, increases in housing density—regardless of zoning changes—are associated with an increase in non-Hispanic Black residents and a decrease in non-Hispanic White residents. These results suggest that there is a break in the chain of inclusion: while increasing the maximum allowable residential density alone is not sufficient to promote racial inclusion, building housing is. Removing this barrier may be a necessary first step to increasing the housing supply, but it must be accompanied by additional efforts to promote housing development to realize its inclusionary goals.


Manuscripts Under Review

  

Sullivan, Laura R. “Developing Moves to Opportunity: Examining Racial Disparities in Residential Attainment among Low-Income Housing Tax Credit Tenants.” Under Review.


Subsidized housing programs play a role in the reproduction of spatial inequality, including the Low-Income Housing Tax Credit (LIHTC). Prior work has shown that LIHTC tenants achieve lower levels of residential attainment, but it is unclear if these experiences differ by race and ethnicity. I use unique residential history data to address the following research questions: (1) Does LIHTC improve access to higher resource areas compared to the private market? (2) To what degree does LIHTC reduce racial disparities in residential attainment? I find that LIHTC tenants have lower probabilities of moving to higher resource areas than low-income private market tenants; however, these aggregated probabilities mask differences by race. White LIHTC tenants are more likely to have higher levels of residential attainment compared to non-White LIHTC tenants. LIHTC does marginally reduce White-Black disparities in moving to opportunity, suggesting that LIHTC has the potential to reduce racial disparities in residential attainment. 


Sullivan, Laura R., Scott W. Allard, Maria V. Wathen, and Lucie Kalousová. “Capacity, Need, and Location: Emergency Food Programs in the Detroit Metropolitan Area.” Under Review.


Nonprofit food pantries provide critical assistance to families experiencing food insecurity, but little is known about food assistance provision across metropolitan areas. We combine unique data on food pantries to examine differential access to food assistance providers in the Detroit metro area. Our data allow us to construct service capacity measures that reflect the realities of the emergency food assistance environment and link these measures to receipt of assistance. We find that urban neighborhoods have access to significantly more pantries and pantries with higher levels of service capacity than suburban neighborhoods when controlling for a neighborhood’s poverty rate. Additionally, households in poverty in urban areas were significantly more likely to receive resources from a food pantry than those in suburban areas. These insights into patterns of access to emergency assistance contribute to a deeper understanding of resource availability in evolving metropolitan areas, with implications for equitable food assistance provision. 


Manuscripts in Preparation

 

Sullivan, Laura R. “What Drives Out-Migration from Upzoned Neighborhoods? Examining the Role of Rent Stabilization in New York City’s Rezoned Areas.”


Sullivan, Laura R. “Neighborhood-level Rezonings and the City’s Role in Allocating Real Estate Benefits: Evidence from New York City.”


Sullivan, Laura R. “Rural Defenders: Developing a Zoning Institution in a Small Town."


Mleczko, Matthew and Laura R. Sullivan. “Address-level Analysis of Neighborhood Integration Dynamics.”


Tach, Laura and Laura R. Sullivan. “The Effects of Federal Place-Based Policies on Child Development & Wellbeing in Disadvantaged Neighborhoods.”

 

Bischoff, Kendra, Lind Shi, Laura R. Sullivan, and Laura Tach. “Risk and Refuge: Exploring Compounding Environmental Vulnerabilities and Climate Migration in California Neighborhoods”


Sullivan, Laura R., Lydia Homandberg, and Matt Hall. “Using consumer trace data to study internal migration in the U.S.”