Conductivity characteristic of international tanker rate fluctuations based on complex networks

Complex network theory and Granger causality test are applied to construct the risk transmission network of international tanker freight rate volatility.Through the dynamic evolution analysis of the network topology,the impact of two major crisis events on the risk spillover effect of freight rate volatility among the segmented routes in the tanker market is investigated.It is found that the crisis events have a significant impact on the network structure of tanker tariff volatility,and after the financial crisis,the tariff linkage effect among the segmented routes is significantly enhanced,and the systematic risk level rises.However,after the outbreak of the epidemic,the tariff linkage risk of the whole tanker market declined,and the tariff risk spillover effect of each segmented ship type weakened.Meanwhile,based on network associations,the Handy-size market has sustained risk spillover effects on other segments,while VLCCs became a source of risk after the financial crisis,and Aframaxes changed to a major source of risk spillover after the epidemic.The findings of the study contribute to a deeper understanding of the patterns of risk transmission between segments of the tanker transportation market.