Research on regional spillover linkage and spatial characteristics of hog price risks: based on the LASSO-VAR modeling

The outbreak of major animal epidemics has strengthened spatial linkages of price risks in the hog market. A comprehensive analysis of regional spillover effects in hog prices helps clarify the spatial spillover dynamics under animal epidemic impacts. Based on monthly provincial hog price data from January 2005 to December 2021 across China, this study applies the LASSO-VAR model and the DY spillover index to investigate regional dynamic spillover effects in hog price risks and characteristics of their spatial network structure. Results reveal that: 1) The overall price risk level in China’s hog market has exhibited a fluctuating trend, with alternating high and low risk periods; risk levels rose significantly during specific periods, particularly during the African swine fever outbreak, when risk volatility surged. 2) Risk spillover effects display significant regional variations: major production provinces act as core risk exporters, while non-major production provinces primarily function as risk importers. The overall risk spillover index follows an inverted “U-shaped” cyclical pattern, with regional risk linkages strengthening markedly during high epidemic incidence phases. And 3) the spatial spillover network of hog price risks shows strong overall connectivity and relative stability; concentrated hog production areas occupy central network positions, with more prominent network influence and control capabilities. By analyzing the spatiotemporal characteristics of risk spillovers, this study provides a theoretical foundation for hog market risk management.