Leveraging Geospatial Data to Understand Social Mixing in Cities

Abstract

Understanding the impact of dense social interactions in urban areas is crucial for designing inclusive cities, as they contribute to both the benefits and challenges of urban living. Various urban planning paradigms and design approaches, such as the 15 minute city, aim to foster social connections and accessibility across communities. However, evaluating the effectiveness of these paradigms is difficult given the complexity of measuring social interactions. In the following projects, I leverage large, geospatial datasets which capture human mobility to describe policy and design impacts on social mixing in three different urban contexts.

Study 1 presents a new way to measure social segregation in mobility patterns using sparse, anonymized geolocation data. We identify homophily in the way that Stockholm residents travel through cities without performing privacy-invasive and data-intensive home location detection. Study 2 calculates this metric with geolocated Twitter data to analyze the impacts of Paris’s “Zones 30” policy, which aimed to enhance human mobility and social mixing by reducing speed limits and implementing street improvements. We find that areas of the city where the policy was implemented fostered more activity from more unique Twitter users who come from more neighborhoods of the city, but not from more socioeconomically diverse neighborhoods of the city. Study 3 employs call detail record data to measure social mixing on a fine spatial and temporal scale across the city of Stockholm, identifying the types of urban amenities that are located in areas where highly income-diverse groups of people gather. We then leverage quasi-random shocks to the road network due to maintenance-based road closures in order to identify causally-interpretable relationships between increasing access to various types of urban amenities and experienced segregation. Study 4 draws on GPS data from mobile phones in order to assess the relationship between local living, as advocated for by the “15-minute city” urban planning paradigm, and experienced socioeconomic segregation across the US. We find that low-income neighborhoods with high levels of local living see lower levels of experienced diversity, indicating a potential tradeoff between the social and environmental goals of the 15-minute city paradigm.

Collectively, these studies highlight the value of fine-grained mobility data in understanding the types of urban spaces and layouts that foster social interactions between diverse groups of people and those that exacerbate social segregation—questions critical to the design of inclusive, sustainable cities.