Impacts of Catchments Derived from Fine-Grained Mobility Data on Spatial Accessibility (Short Paper)

Authors Alexander Michels , Jinwoo Park , Bo Li, Jeon-Young Kang , Shaowen Wang

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Author Details

Alexander Michels
  • CyberGIS Center for Advanced Digital and Spatial Studies, University of Illinois Urbana-Champaign, IL, USA
Jinwoo Park
  • CyberGIS Center for Advanced Digital and Spatial Studies, University of Illinois Urbana-Champaign, IL, USA
Bo Li
  • Department of Statistics, University of Illinois Urbana-Champaign, IL, USA
Jeon-Young Kang
  • Department of Geography, Kyung Hee University, Dongdaemun-gu, Seoul, South Korea
Shaowen Wang
  • CyberGIS Center for Advanced Digital and Spatial Studies, University of Illinois Urbana-Champaign, IL, USA

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Alexander Michels, Jinwoo Park, Bo Li, Jeon-Young Kang, and Shaowen Wang. Impacts of Catchments Derived from Fine-Grained Mobility Data on Spatial Accessibility (Short Paper). In 12th International Conference on Geographic Information Science (GIScience 2023). Leibniz International Proceedings in Informatics (LIPIcs), Volume 277, pp. 52:1-52:6, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2023)


Spatial accessibility is a powerful tool for understanding how access to important services and resources varies across space. While spatial accessibility methods traditionally rely on origin-destination matrices between centroids of administrative zones, recent work has examined creating polygonal catchments - areas within a travel-time threshold - from point-based fine-grained mobility data. In this paper, we investigate the difference between the convex hull and alpha shape algorithms for determining catchment areas and how this affects the results of spatial accessibility analyses. Our analysis shows that the choice of how we define a catchment produces differences in the measured accessibility which correlate with social vulnerability. These findings highlight the importance of evaluating and communicating minor methodological choices in spatial accessibility analyses.

Subject Classification

ACM Subject Classification
  • Applied computing → Earth and atmospheric sciences
  • Applied computing → Health informatics
  • Applied computing → Transportation
  • Spatial accessibility
  • alpha shape
  • convex hull
  • cyberGIS
  • social vulnerability


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