Evaluating context-dependent efficiency of the marine transport industry

Purpose The main objective of this research is not only to evaluate the efficiency of shipping companies pre- and post-COVID-19 outbreak but also considers the negative impact on the environment produced by shipping activities pre- and post-IMO 2020 regulation. This research not only investigates the traditional aspect of operational efficiency and financial efficiency as well as the negative impact on the environment produced by shipping activities. It also tests if joining a strategic alliance affects the efficiency of shipping companies. Design/methodology/approach This research applies the non-separable slacks-based measure (SBM)-data envelopment analysis (DEA) model (Tone and Tsutsui, 2006) and the context-dependent DEA scheme (Seiford and Zhu, 2003) to evaluate and rank the efficiency of 38 shipping companies during 2019 and 2020 (pre- and post-COVID-19 outbreak and pre- and post-IMO 2020 regulation). The Mann–Whitney U test is further applied to examine differences between alliance and non-alliance companies. Findings The results indicate that, during the COVID-19 pandemic, alliance-affiliated companies exhibited greater resilience, maintaining relatively stable efficiency levels, whereas non-alliance companies experienced more pronounced fluctuations. The smaller decline in efficiency among alliance companies suggests a buffering effect under external shocks. Furthermore, when environmental efficiency is incorporated into the analysis, alliance companies significantly outperform non-alliance companies, indicating a stronger capacity to adapt to both operational adjustments and environmental constraints. Originality/value This research contributes to the literature by integrating environmental (undesirable output) considerations into efficiency analysis within a context-dependent DEA framework. It provides a comprehensive evaluation of operational, financial and environmental efficiency simultaneously and offers new insights into the role of strategic alliances in enhancing resilience and sustainability in the marine transport industry.