Using topological analysis to map quality and nuisance access in cities
Using Persistent Homology to Analyze Access to Heterogeneous-Quality Resources and Heterogeneous-Severity Nuisances
Computational Geometry
Summary
Access to resources like parks or exposure to nuisances like landfills in cities can vary in quality and severity across different areas. This paper introduces a method that uses a type of math called persistent homology to better capture these variations and analyze geographic patterns of access and exposure. Unlike older approaches, this method considers multiple factors at once, helping identify clusters where people experience poor access or overexposure. They applied this to Chicago to find areas with poor park access, landfill exposure, and unusual pub and bar exposure.
What this means in practice
- •For urban planners: Identify geographic clusters of low-quality resource access and high-severity nuisances to better target city planning and interventions.
- •For public health officials: Detect areas with overexposure to environmental nuisances to prioritize health risk mitigation efforts.
Tested on one dataset.
Authors
Sarah Tymochko, Gillian Grindstaff, Abigail Hickok, Jiajie Luo, Mason A. Porter
Abstract
We develop a framework to use multiparameter persistent homology (PH) to examine access to heterogeneous-quality resources and exposure to heterogeneous-severity nuisances in a geographic region. Persistent homology, which is a type of topological data analysis {(TDA)}, has been employed previously to examine resource coverage. Unlike prior approaches, which used one-parameter PH to study resource coverage and nuisance exposure, our method accounts for heterogeneous-quality resources. Our framework, which employs a computationally-efficient approximation of multiparameter PH, allows one to study access to any resource ({or} exposure of any nuisance) using any notion of quality (or severity). Using the city of Chicago as an example region, we employ our framework to detect clusters of poor access to public parks, overexposure to landfills, and both underexposure and overexposure to pubs and bars.