The effect of liner shipping connectivity on green export performance: heterogeneous evidence from higher-income and lower-income exporters

Purpose This study examines the association between bilateral liner shipping connectivity and green export performance, with particular attention to the extensive and intensive margins of green trade across higher-income and lower-income exporters. Design/methodology/approach Drawing on lists of environmentally friendly products provided by the OECD, WTO and APEC, this study compiles a dataset of 485 green goods identified at the six-digit level under the HS2002 classification. The analysis employs the Poisson Pseudo-Maximum Likelihood (PPML) estimation within a gravity model framework, using bilateral data from 150 countries over 2006–2021. Findings The empirical results indicate that stronger bilateral liner shipping connectivity is positively associated with green export performance. Specifically, a one-unit increase in the rescaled bilateral liner shipping connectivity index is associated with approximately a 35.7% increase in green export market share and a 3.44% increase in bilateral green export value. The findings also reveal heterogeneous patterns across subsamples. For higher-income exporters, liner shipping connectivity is positively correlated with the intensive margin but negatively associated with the extensive margin. For lower-income exporters, connectivity shows positive associations with both trade margins. These results are robust after addressing endogeneity using a control-function PPML approach. Originality/value This study offers novel evidence on the association between liner shipping connectivity and green export performance through both the extensive and intensive margins of trade across higher-income and lower-income exporters, thereby providing valuable insights for targeted green trade and maritime policies.