“…One important idea in the shipping industry is the measurement of the environmental efficiency of shipping companies. Researchers have lately applied DEA as a favored method in measuring the eco-efficiency (Emrouznejad & Yang, 2018;Kao, 2014;Sueyoshi, Yuan, & Goto, 2017) of plants (Lozano, 2017;Sueyoshi & Goto, 2012), industrial parks (Fan et al, 2017), provinces or regions (Song, Peng, Wang, & Zhao, 2018;Wu, Zhu, Ji, Chu, & Liang, 2016;Zhang, Bi, Fan, Yuan, & Ge, 2008), and industrial sectors (Shao, Yu, & Feng, 2019). Chen et al (2018) and Gong et al (2019) evaluate the efficiency of major shipping carriers considering the negative impact of emissions.…”