Network-based method for ranking of efficient units in two-stage DEA models

Abstract

This study presents a methodology that is able to further discriminate the efficient decision-making units (DMUs) in a two-stage data envelopment analysis (DEA) context. The methodology is an extension of the single-stage network-based ranking method, which utilizes the eigenvector centrality concept in social network analysis to determine the rank of efficient DMUs. The mathematical formulation for the method to work under the two-stage DEA context is laid out and then applied to a real-world problem. In addition to its basic ranking function, the exercise highlights two particular features of the method that are not available in standard DEA: suggesting a benchmark unit for each input/intermediate/output factor, and identifying the strengths of each efficient unit. With the methodology, the value of DEA greatly increases.

Keywords:

• data envelopment analysis
• two-stage DEA
• network-based ranking method
• network centrality

Acknowledgements

The authors would like to thank anonymous referees for their constructive comments that have much improved the readability of this article. This work is in part supported by Taiwan’s National Science Council grant NSC 99-2410-H-011-003.