Evaluation of international maritime network configuration and impact of port cooperation on port hierarchy

The objective of this study is to evaluate the impact of port cooperation on port hierarchy based on network analysis. Specifically, several complex network measures and link predictions using graph embedding are applied. Container ports have intensified the competition for higher positions in the port hierarchy because ports in the higher port hierarchy contribute to the economic development of port regions as the central point of container cargo trade. In this competitive situation, ports, especially those in proximity, build cooperative relationships to achieve higher competitiveness through synergy, such as economies of scale. We analyze the hierarchy of the aggregated Hanshin port (Kobe and Osaka, Japan) in the Japanese cargo network compared to a strong competitor, the Busan port (Korea). We find that building cooperative relationships contributes to a higher position in the port hierarchy and affects the network configuration, such as creating a higher interconnection of ports as a community structure. However, cooperation alone does not produce a higher position in the port hierarchy than a strong competitor. This study can assist policymakers engaged in port management in attaining higher positions in the port hierarchy through port cooperation. In particular, the results are valuable in areas with network configurations similar to the Japanese cargo network, which have nearby dominant hub ports, such as Busan.