Environmental efficiency measures for ports: an application of RAM-Tobit-RAM with undesirable outputs

ABSTRACT

In this paper, the environmental efficiency of the ports is measured. Labour, fund and infrastructure input are selected as the inputs, container throughput, cargo throughput and main business income are selected as the outputs, CO₂ emission is chosen as the undesirable output. A new model—RAM-Tobit-RAM (Range Adjusted Measure) with undesirable outputs is built to evaluate the environmental efficiency. Ten Chinese ports from 2004 to 2013 are taken as the samples to verify its rationality. The results suggest that it is not necessarily beneficial for environmental efficiency to expand the port scale.

KEYWORDS:

• Environmental efficiency
• RAM-Tobit-RAM
• undesirable outputs
• port
• non-operational factors

Acknowledgements

We are grateful to the anonymous reviewers for their constructive comments which improved this paper significantly. This work was supported by National Nature Science Foundation of China: (Nos.71403034 and 71521002), Nature Science Foundation of Liaoning Province (No.201601841), China Postdoctoral Science Foundation (No. 2016M590050) and National Key R&D Program (2016YFA0602603).

Disclosure statement

No potential conflict of interest was reported by the author.

Additional information

Funding

This work was supported by National Natural Science Foundation of China: [Nos.71403034 and 71521002], Natural Science Foundation of Liaoning Province [No.201601841], China Postdoctoral Science Foundation [No. 2016M590050] and National Key R&D Program [2016YFA0602603].