Coupling mechanism and coupling linkage effect between multiplex city networks - a case study of the Chengdu-Chongqing city cluster

The city functions as a quintessential complex giant system, characterized by subsystems that both compete and cooperate with one another. These subsystems interact and interconnect to create higher-level city complex systems, exhibiting intricate nonlinear coupling relationships among city networks of varying natures. This paper introduces a comprehensive research framework, termed Correlation - Multiplex coupling network - Coupling linkage effect evaluation (CMC). This framework offers a novel perspective for the study of city networks by integrating the multiplex networks and coupling degree models. It enables an examination of the coupling effects arising from the interactions between multiplex networks on city complex systems and city networks. Using the Chengdu-Chongqing city cluster as a case study, this research analyzes the nonlinear coupling relationship between the enterprise network and the information network. The results show that: (1) There is a complex nonlinear coupling relationship between city enterprise network and information network. (2) From 2011 to 2020, the city networks within the Chengdu-Chongqing city cluster exhibited a distinctive dual-core pattern, characterized by a notable 'Rich Club' phenomenon (That is, nodes with high centrality tend to connect with nodes with high centrality) and the 'Matthew effect'. The coupling network, influenced predominantly by the enterprise network, demonstrated a gradual increase in complexity, building upon the inherited dual-core characteristics of the individual networks. (3) From 2011 to 2020, a discernible difference emerged between the node coupling linkage effect and the link coupling linkage effect: the former predominantly exhibited a low to medium level, while the latter was primarily at a medium level with a declining trend. In 2020, the profound impact of the COVID-19 epidemic led to the weakening of network coupling. Enhancing the coupling and linkage among multiplex city networks provides a valuable scientific reference for advancing regional high-quality development.