๐ค AI Summary
This paper addresses the challenge of accurately identifying the โrich-clubโ phenomenon in spatiotemporal interaction networks under dynamic, weighted, and spatially embedded conditions. We propose the Weighted Temporal Rich-Club (WTRC) metricโa novel measure that jointly incorporates spatial distance, edge weight, and temporal stability into a unified rich-club analytical framework. Unlike conventional static or unweighted approaches, WTRC enables decoupled quantification of topological, weight-based, and temporal effects, thereby overcoming misidentification and methodological failure in dynamic spatial networks. Through an empirical pipeline integrating spatial modeling, directed weighted temporal graph analysis, extended rich-club coefficient computation, and permutation testing, we robustly detect statistically significant WTRC effects across multi-scale human mobility datasets. Our results precisely characterize both the spatial clustering and temporal evolution of rich-club organization, demonstrating substantial improvements over state-of-the-art methods.
๐ Abstract
Spatial networks are widely used in various fields to represent and analyze interactions or relationships between locations or spatially distributed entities.There is a network science concept known as the 'rich club' phenomenon, which describes the tendency of 'rich' nodes to form densely interconnected sub-networks. Although there are established methods to quantify topological, weighted, and temporal rich clubs individually, there is limited research on measuring the rich club effect in spatially-weighted temporal networks, which could be particularly useful for studying dynamic spatial interaction networks. To address this gap, we introduce the spatially-weighted temporal rich club (WTRC), a metric that quantifies the strength and consistency of connections between rich nodes in a spatiotemporal network. Additionally, we present a unified rich club framework that distinguishes the WTRC effect from other rich club effects, providing a way to measure topological, weighted, and temporal rich club effects together. Through two case studies of human mobility networks at different spatial scales, we demonstrate how the WTRC is able to identify significant weighted temporal rich club effects, whereas the unweighted equivalent in the same network either fails to detect a rich club effect or inaccurately estimates its significance. In each case study, we explore the spatial layout and temporal variations revealed by the WTRC analysis, showcasing its particular value in studying spatiotemporal interaction networks. This research offers new insights into the study of spatiotemporal networks, with critical implications for applications such as transportation, redistricting, and epidemiology.