Estimation of congestion in free disposal hull models using data envelopment analysis.

M Abbasi,F Hosseinzadeh Lotfi,G R Jahanshahloo,M Rostamy-Malkhlifeh

doi:10.1155/2014/427673

M Abbasi, F Hosseinzadeh Lotfi + Show 2 more

Open Access

https://doi.org/10.1155/2014/427673

Copy DOI

Journal: TheScientificWorldJournal	Publication Date: Jan 1, 2014
Citations: 17	License type: CC BY 3.0

Affiliation: Islamic Azad University, Tehran

Abstract

This paper deals with evaluating congestion in free disposal hull (FDH) models. There are several approaches in data envelopment analysis (DEA) literatures which discuss the theory and application of congestion. However, almost all of these approaches considered convex DEA technologies. So, in the case of nonconvex technologies, including FDH technology, this field is almost nil. This paper makes an attempt to fill in this void. To do so, this study provides a pairwise comparisons-based algorithm to evaluate congestion in FDH model. This algorithm identifies the sources of congestion and estimates its amounts. It is also capable of detecting the losses amounts of output due to congestion. The validity of the proposed model is demonstrated using some numerical and empirical examples.

Highlights

Evaluation of decision making units (DMUs) is an important task especially from a managerial point of view
Khodabakhshi [11] provided a one-model approach of input congestion based on input relaxation model
Afterwards, we provide a polynomial time algorithm based on pairwise comparisons which evaluates congestion for DMUs using certain differences of inputs and outputs

Summary

Introduction

Evaluation of decision making units (DMUs) is an important task especially from a managerial point of view. Khodabakhshi [11] provided a one-model approach of input congestion based on input relaxation model. The targets resulting from efficiency assessment correspond to the points on the continuous efficiency frontiers This means that DMUs might be compared with unreal DMUs which sometimes is meaningless in real life, for example, when we want to evaluate the efficiency of various car engines. We first present definitions of output efficiency for DMUs under a series of DEA output additive models Using these definitions, we develop a necessary and sufficient condition for existence of congestion in FDH model. Afterwards, we provide a polynomial time algorithm based on pairwise comparisons which evaluates congestion for DMUs using certain differences of inputs and outputs.

Preliminaries

Congestion in FDH Model

Numerical Examples

Conclusion