Case studies in industry and services
Kh. Ghaziyani; farhad hosseinzadeh Lotfi; Sohrab Kordrostami; alireza amirteimoori
Abstract
Today, one of the main problems in many organizations such as banks with many branches, is that the method of evaluating them is not correct. The traditional techniques used to evaluate performance are often single-level and do not provide the manager with enough information to identify the inefficiency ...
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Today, one of the main problems in many organizations such as banks with many branches, is that the method of evaluating them is not correct. The traditional techniques used to evaluate performance are often single-level and do not provide the manager with enough information to identify the inefficiency causes of inefficient units. In contrast, Bi-level Data Envelopment Analysis (DEA) models solve the problem of ignoring internal relationships. In this paper, first, the factors that had a higher rank were selected as input and output factors with the help of bank experts and the AHP method. Then, the performance of 30 branches of the Central Bank of Iran was evaluated using the leader-follower method and generalizing Russell's non-radial method. In this paper, the intermediate data is desirable and undesirable. The results showed that the proposed model does not have the problems of traditional models and provides a more realistic assessment of the efficiency of bank branches.
Data Envelopment Analysis, DEA
Sima Madadi; Farhad Hosseinzadeh Lotfi; Mehdi Fallah Jellodar; Mohsen Rostamy-Malkhalifeh
Abstract
We developed a DEA-based resource re-allocation model based on environmental DEA technology for organizations with a central decision-making environment. The proposed model considered a weak disposability axiom for undesirable outputs and combined Data Envelopment Analysis (DEA) with Multiple-Objective ...
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We developed a DEA-based resource re-allocation model based on environmental DEA technology for organizations with a central decision-making environment. The proposed model considered a weak disposability axiom for undesirable outputs and combined Data Envelopment Analysis (DEA) with Multiple-Objective Programing (MOP). The objective was to find the appropriate re-allocation model in order to save energy and reduce environmental pollution, so that the next steps could be taken toward improvement. Given that reducing the inputs and outputs of inefficient units is sometimes not achievable and does not seem logical, for the reduction in the values to be logical and achievable, we divided the Decision-Making Units (DMUs) into different levels of efficient frontier using the context-dependent DEA technique. For this purpose, the model was designed to move the DMUs from the current frontier to the efficient frontier of the previous layer, which has better efficiency conditions, or keep them on their own frontier. In addition, the opinion of the central decision maker regarding the amount of reduction in the inputs and outputs was expressed using Goal Programing (GP) in a way that does not make the model infeasible. By implementing the model in 8 regions of the world, suggestions were made regarding the amounts of energy saving and CO2 pollution reduction based on the conditions determined by the central decision maker aiming improve the efficiency of inefficient units in the next step.
Game theory
Fatemeh Ghaeminasab; Mohsen Rostamy-Malkhalifeh; Farhad Hosseinzadeh Lotfi; Mohammad-Hasan Behzadi; Hamidreza Navidi
Abstract
In this paper, while taking into account the cooperative relationships between units, the problem of revenue allocation is considered as a coalitional game. In order for the allocation to be equitable, by relying on the concept of DEA efficiency, a new characteristic function is presented, and then using ...
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In this paper, while taking into account the cooperative relationships between units, the problem of revenue allocation is considered as a coalitional game. In order for the allocation to be equitable, by relying on the concept of DEA efficiency, a new characteristic function is presented, and then using the concept of the Shapley value, which is a well-recognized concept in coalitional game theory, a unique solution is obtained for the revenue allocation problem. And finally, to evaluate the equitability of the performed revenue allocation, the Gini coefficient is utilized. A comparison of the Gini coefficient obtained for our method with those of some existing methods showed that our method is more equitable than the previous ones. This demonstrates how impactful the wise and accurate selection of the characteristic function is in the equitability of the results.
Data Envelopment Analysis, DEA
Jafar Pourmahmoud; Naser Kaheh; Farhad Hosseinzadeh Lotfi
Abstract
In traditional cost-efficiency models, inputs and outputs, as well as input prices were known as constant values for each decision-making unit In our daily applications, however, market entry prices vary at different times. In other words, input prices for decision-making units (DMUs) are time dependent. ...
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In traditional cost-efficiency models, inputs and outputs, as well as input prices were known as constant values for each decision-making unit In our daily applications, however, market entry prices vary at different times. In other words, input prices for decision-making units (DMUs) are time dependent. Traditional methods cannot calculate the cost efficiency of DMUs with time-dependent prices. This paper proposes a new method to calculate the cost efficiency of DMUs in the presence of time-dependent prices. The proposed model is a parametric programming problem model depending on time. In the presented model, the inputs and outputs are functions in terms of time, which is not present in the models introduced by other researchers. New definitions for time-dependent cost efficiency have also been introduced. The cost efficiency of DMUs is measured over a given time and the units are ranked according to the time obtained. Finally, a numerical example has been presented to illustrate the proposed method.
Data Envelopment Analysis, DEA
Seyede Nasrin Hosseini Monfared; Farhad Hosseinzadeh Lotfi; Mohammad Reza Mozaffari; Mohsen Rostamy Malkhalifeh
Abstract
In conventional DEA models, it is supposed real-valued inputs and outputs while every measure must be determined as an input or output. However, in some cases, there are flexible measures which can only take integer values in two-stage network DEA. In all previous researches has not been mentioned the ...
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In conventional DEA models, it is supposed real-valued inputs and outputs while every measure must be determined as an input or output. However, in some cases, there are flexible measures which can only take integer values in two-stage network DEA. In all previous researches has not been mentioned the classification flexible measures while some inputs, outputs, and flexible measures can only take integer values in two-stage network DEA. So in this paper, we propose integer-valued FNDEA approach is based on envelopment form of CCR that evaluates the relative efficiency of DMUs and determines the status of flexible measures in the presence of integer data in basic and general two-stage network structures. Our model can determine projection points of inputs, outputs, and flexible measures in the presence of integer data in two-stage network DEA. Numerical examples are used to illustrate the procedure.
Sahar Khoshfetrat; Farhad Hosseinzadeh Lotfi
Volume 1, Issue 1 , March 2014, , Pages 12-18
Abstract
As ranking is one of the most important issues in data envelopment analysis (DEA), many researchers have comprehensive studies on the subject and presented different approaches. In some papers, DEA and Analytic hierarchy process (AHP) are integrated to rank the alternatives. AHP utilizes pairwise comparisons ...
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As ranking is one of the most important issues in data envelopment analysis (DEA), many researchers have comprehensive studies on the subject and presented different approaches. In some papers, DEA and Analytic hierarchy process (AHP) are integrated to rank the alternatives. AHP utilizes pairwise comparisons between criteria and units, assessed subjectively by the decision maker, to rank the units. In this paper, a nonlinear programming (NLP) model is introduced to derive the true weights for pairwise comparison matrices in AHP. Genetic algorithm (GA) is used in order to solve this model. We use MATLAB software to solve proposed model for ranking the alternatives in AHP. A numerical example is applied to illustrate the proposed model.