Reconceptualising regional boundaries: depicting blurred regions in China through individual mobility data

Abstract

Delineating the boundary or impact area of an economic, cultural, or lifestyle region has been a long-lasting problem in urban and regional geography. The fundamental difficulty lies in the exact definition of a region, and what criteria need to be considered. Existing methods either use criterion-based definitions or network-based measures to evaluate the affiliation of a city to a region. However, both types of methods only give static and definitive results but ignore the dynamism and graduality between regions. In this paper, we propose a Singular Value Decomposition (SVD)-based method to depict the impact areas of regions in China using individual connections among cities. Using the individual mobility data from an online map service, we decompose the mobility patterns of China into a series of eigen-mobility-patterns—each corresponds to the impact area of a city, or a mobility-based region. The overlay of multiple eigen-mobility patterns depicts the “blurred” boundary between the respective regions—or their competing hinterlands. We hope the method could be used to help understand the complexity of drawing regional boundaries and help policymakers to identify the non-confined but blurred economic and cultural landscape of various contexts in regional governance.

Keywords

Regional Boundary / Singular Value Decomposition / Eigen-Mobility-Pattern / China

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Funding

Peking University Institute of Public Governance

PKU-WUHAN Institute for Artificial Intelligence

RIGHTS & PERMISSIONS

The Author(s)