Crowdsourcing the Robin Hood effect in cities

TL;DR

This study proposes a low-effort, mobility-based approach to reduce socioeconomic inequalities in cities by slightly redirecting shopping trips, which can be supported by mobile apps to promote equitable opportunity distribution.

Contribution

It introduces a novel, data-driven method to enhance spatial equity through minimal changes in shopping mobility, leveraging anonymized credit card data from Madrid and Barcelona.

Findings

Only about 5% of shopping trips need redirection to achieve equity.

Redirection preserves key mobility properties like travel distances.

The approach also improves sustainability indicators.

Abstract

Socioeconomic inequalities in cities are embedded in space and result in neighborhood effects, whose harmful consequences have proved very hard to counterbalance efficiently by planning policies alone. Considering redistribution of money flows as a first step toward improved spatial equity, we study a bottom-up approach that would rely on a slight evolution of shopping mobility practices. Building on a database of anonymized credit card transactions in Madrid and Barcelona, we quantify the mobility effort required to reach a reference situation where commercial income is evenly shared among neighborhoods. The redirections of shopping trips preserve key properties of human mobility, including travel distances. Surprisingly, for both cities only a small fraction ($\sim 5 \%$) of trips need to be altered to reach equity situations, improving even other sustainability indicators. The method could be implemented in mobile applications that would assist individuals in reshaping their shopping practices, to promote the spatial redistribution of opportunities in the city.