International Journal of Data Envelopment Analysis and *Operations Research*, 2014, Vol. 1, No. 1, 1-11
Available online at http://pubs.sciepub.com/ijdeaor/1/1/1
© Science and Education Publishing
DOI:10.12691/ijdeaor-1-1-1
Measuring Efficiency and Effectiveness for Non-Storable
Commodities: A Mixed Separate Data Envelopment
Analysis Spproaches with Real and Fuzzy Data
Babooshka Shavazipour
*
Department of Mathematics, Mashhad Branch, Islamic Azad University, Mashhad, Iran
*Corresponding author: b.shavazipour@gmail.com
Received November 15, 2013; Revised January 12, 2014; Accepted January 21, 2014
Abstract Data Envelopment Analysis (DEA) is a technique for measuring the relative efficiency of Decision
Making Units (DMUs) which produce similar products. Measures of both technical efficiency and service
effectiveness for storable commodities are essentially the same. However, these measures for non-storable
commodities, such as transport services, represent two distinct dimensions and a joint measurement of both or
measurement with their impression mutual is necessary to fully capture the overall performance. In this paper, a
Mixed Separate Data Envelopment Analysis (MSDEA) approach is introduced to analyze the overall performance of
non-storable commodities. Then, the case of ten intercity car companies is described as the application of this novel
approach. Moreover, when some observations are fuzzy, the efficiencies and effectiveness become fuzzy as well.
For more extension, MSDEA approach with fuzzy observations called Fuzzy Mixed Separate Data Envelopment
Analysis (FMSDEA) approach will be presented and illustrated with a numerical example.
Keywords: Data Envelopment Analysis (DEA), efficiency, effectiveness, Mixed Separate DEA (MSDEA), fuzzy
data
Cite This Article: Babooshka Shavazipour, “Measuring Efficiency and Effectiveness for Non-Storable
Commodities: A Mixed Separate Data Envelopment Analysis Spproaches with Real and Fuzzy Data.”
International Journal of Data Envelopment Analysis and *Operations Research* vol. 1, no. 1 (2014): 1-11. doi:
10.12691/ijdeaor-1-1-1.
1. Introduction
Data Envelopment Analysis (DEA) is a technique for
measuring the relative efficiency of Decision Making
Units (DMUs) which produce similar products. Measures
of both technical efficiency (a transformation of factors to
production) and service effectiveness (consumption of
production) for storable commodities are essentially the
same because of the commodities, once produced, can be
stockpiled until consumed. Nothing will be lost
throughout the transformation from production to
consumption if one assumes that all the stockpiles are
eventually sold, there is no storage cost, and there is no
loss incurred. Namely, conventional measures for storable
commodities assume perfect sale and no storage cost
effectiveness. However, technical efficiency and service
effectiveness for non-storable commodities, such as
transport services, represent two distinct measurements
because one can never store the surplus service during
periods of low demand (off peak hours) for use during
periods of high demand (peak hours). When such non-
storable commodities are produced and a portion of which
are not concurrently consumed, the technical effectiveness
(a joint effect of both technical efficiency and service
effectiveness) would be less than the technical efficiency.
Over the past three decades, various DEA models have
been widely used to evaluate the technical efficiency or
technical effectiveness of DMUs in different organizations
or industries. In transport performance evaluation,
numerous applications of DEA have also been found in
various fields.
In order to completely and fairly evaluate the relative
performance of non-storable transport services, several
recent works have employed various DEA approaches to
evaluating the efficiency and effectiveness. In general,
they can be divided into five categories: separate DEA
model (hereinafter, SDEA; e.g. [1,2]), separate two-stage
DEA model (hereinafter, STDEA; e.g. [3,4,5]), network
DEA model (hereinafter, NDEA; e.g. [6,7,8]), integrated
two-stage DEA model (hereinafter, ITDEA; e.g.
[9,10,11]), and integrated DEA model (hereinafter, IDEA;
e.g. [12]). The SDEA employs independent DEA models
to measure technical efficiency, service effectiveness, and
technical effectiveness separately. Hence, paradoxical
improvement strategies were usually generated based on
the results of these independent DEA models. To
overcome this shortcoming, the STDEA uses an input-
oriented DEA model to evaluate the technical efficiency
and an output-oriented DEA model to assess the service
effectiveness, holding the output level unchanged.
Although the STDEA model will not generate conflicting
improvement strategies, it suggests the organization be