This paper presents a method for performance evaluation, ranking and clustering based on the double-frontier view to analyze the complex networks. The model allows us to open the structure of the “black box” and can help to obtain important information about More
This paper presents a method for performance evaluation, ranking and clustering based on the double-frontier view to analyze the complex networks. The model allows us to open the structure of the “black box” and can help to obtain important information about efficient and inefficient points of the system. In this paper, we consider a three-stage network, in respect to the additional desirable and undesirable inputs and outputs and utilize the cooperative approach to measure the efficiency of the overall system. Due to the fact that, a conclusion implying only one of these two, optimistic or pessimistic views is one-sided and incomplete, so, in this paper we used the double-frontier to analyze the network. Moreover, a heuristic technique was used to convert non-linear models into linear models. After obtaining the effective and inefficient points of the network, the DMUs are classified into several clusters by the k-means algorithm.Finally, in this article, in order to apply the proposed model a factory producing dairy products with a production area, warehouse premises and a delivery point are simulated. This factory has been regarded as a dynamic network with a time period of 24 intervals. The results of the ranking showed that, the time periods, (10) and (1) were the best and poorest respectively, in context to the efficiency within 24 phases of time.
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In many organizations and financial institutions, we don't always have acsses to inputs and outputs to evaluate the decision-making units (DMUs), but rather only a ratio of inputs to outputs ( or reverse) might be available. In DEA, cost efficiency determines input stan More
In many organizations and financial institutions, we don't always have acsses to inputs and outputs to evaluate the decision-making units (DMUs), but rather only a ratio of inputs to outputs ( or reverse) might be available. In DEA, cost efficiency determines input standards based on input costs. In multi-stage network DEA processes, in addition to input standards, cost efficiency would determine the standards for intermediate vectors as well as using linear programming models. In this paper, we calculated efficiency values for each stage, as well as overall efficiency based on a proxuction possibility set (PPS) in three stage network DEA-R processes. Then, we suggest three stage network DEA-R (ratio-based DEA midel) processes which are a combination of data envelopment analysis (DEA) and ratio data then we will propose cost efficiency models in each three stage network DEA-R process. Afterthan, we will determine the standards for outputs and intermediate measures in each stage using the subject of cost efficiency . In the end, overall efficiency and cost efficiency will be evaluated among of 30 Iranian educational research centers during the first half- year of 2015 based on a three stage network DEA-R process.
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A new approach or model to the dynamic DEA, referred to as the adjusted dynamic DEA, is proposed in this study. Adjusted dynamic DEA optimizes the production activity of DMUs by introducing adjustment variables to modify the interconnecting activities between consecutiv More
A new approach or model to the dynamic DEA, referred to as the adjusted dynamic DEA, is proposed in this study. Adjusted dynamic DEA optimizes the production activity of DMUs by introducing adjustment variables to modify the interconnecting activities between consecutive terms, solving conflicts that arise between terms and between management and shareholders. The non-oriented SBM model is used as a base model and is extended to the adjusted dynamic framework, where adjustment variables are introduced. In order to examine the applicability of the proposed method, the model is applied to evaluate the efficiency of ten branches of ten branches of an Iranian bank during three consecutive terms. The adjusted dynamic SBM model under variable return to scale (VRS) is solved and reference units for each inefficient DMU are identified. In addition, the slacks and adjustment variables are analyzed and further suggestions about the efficient conditions to the management are provided.
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این مقاله در ارتباط با مبحث الگویابی برای واحد تصمیم گیرنده سه مرحله می باشد. ابتدا تراکم در واحد شناسایی می شود و حذف می گردد، بدین ترتیب مقادیر تعدیل شده برای محصولات میانی و ورودی های اولیه سیستم بدست می آید. این مقادیر تعدیل شده، که منجر به مغلوب کردن مقادیر ج More
این مقاله در ارتباط با مبحث الگویابی برای واحد تصمیم گیرنده سه مرحله می باشد. ابتدا تراکم در واحد شناسایی می شود و حذف می گردد، بدین ترتیب مقادیر تعدیل شده برای محصولات میانی و ورودی های اولیه سیستم بدست می آید. این مقادیر تعدیل شده، که منجر به مغلوب کردن مقادیر جاری و تعیین کردن نقطه الگو حاصل می شوند، با استفاده از مدل معکوس DEA حاصل می شود که یکی از مهم ترین بخش های این مقاله است. این فرآیند در دو حالت مجزا اتفاق می افتد: حالت اول اینکه کارایی کل سیستم ثابت می ماند و حالت دوم اینکه کارایی کلی سیستم درصدی بهبود دارد.
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In many situations, the performance and the changes of outputs related to dynamic systems should be estimated while the convexity property is relaxed. Accordingly, first, a dynamic free disposal hull (FDH) model is proposed in this paper to address the efficiency of pro More
In many situations, the performance and the changes of outputs related to dynamic systems should be estimated while the convexity property is relaxed. Accordingly, first, a dynamic free disposal hull (FDH) model is proposed in this paper to address the efficiency of processes in multiple period of time while the convexity assumption is unsatisfied. Also, two problems, including a mixed integer linear programming and a linear programming model are provided to compute the dynamic FDH model that is a mixed integer non-linear programming problem. Then the changes of multi-period outputs are dealt with for changes of inputs related to several periods using the proposed inverse dynamic FDH model while the efficiency levels are preserved. A case study of gas industry is, moreover, presented to demonstrate the introduced models. The results show the proposed technique is useful to analyze the performance and to estimate outputs in dynamic processes without including convexity.
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Traditional DEA models deal with measurements of relative eciency ofDMUs regarding multiple - inputs VS. multiple-outputs. One of the drawbacksof these model is the neglect of intermediate products or linkong activities. Af-ter pointing out needs for inclusion of them More
Traditional DEA models deal with measurements of relative eciency ofDMUs regarding multiple - inputs VS. multiple-outputs. One of the drawbacksof these model is the neglect of intermediate products or linkong activities. Af-ter pointing out needs for inclusion of them to DEA models. We propose hybridmodel that can deal with intermediate products formally using this model wecan evaluate divisional eciency of decision making units (DMU) and we showthis model with an example.
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Data envelopment analysis has been in the center of attention due to independency of the production function. But the initial models of data envelopment analysis are incapable of examining the internal structure of the units and have a black-box view. One of the most co More
Data envelopment analysis has been in the center of attention due to independency of the production function. But the initial models of data envelopment analysis are incapable of examining the internal structure of the units and have a black-box view. One of the most common network structures is consecutive two-staged structure. Available models for evaluating this structure are mainly based on the decomposition approach, in other words, their priority is overall efficiency, and the efficiency of the stages is obtained by decomposing the total efficiency. In this paper, an attempt is made to develop a multivariate model that simultaneously considers the overall efficiency and efficiency of the stages. In addition, for multi-response mode, the models were developed to calculate the efficiencies and it was proved that in all models, efficiency scores range from zero to one, and a unit is efficient if only it is efficient in both stages. The presented models were used in an applied example and the results showed that the existing model performed more realistic evaluation than traditional models.
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In this paper, data envelopment analysis (DEA) was discussed for non-homogenous mixed network structure where the outputs of each stage can enter the next stage in the same or another layer as inputs or come out from the system as final products. In this model, in addit More
In this paper, data envelopment analysis (DEA) was discussed for non-homogenous mixed network structure where the outputs of each stage can enter the next stage in the same or another layer as inputs or come out from the system as final products. In this model, in addition to intermediate inputs, each stage can also have independent inputs. For this purpose, a mathematical model has been developed in which the independent inputs and final outputs for the components of the decision making units (DMUs) are examined. To show the efficiency of the model, real data for 20 DMUs were used and the results were compared with those of traditional models. The results obtained from the proposed method eliminate the shortcomings of traditional methods for proper detection of units that are on the efficient border (with an efficiency of one). The developed method can provide the managers and decision makers with a more accurate understanding of the performance of components of DMUs.
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Facility location problems are one of the most important issues for healthcare organizations and centers to achieve social welfare and respond to customer needs. Proper distribution of health and treatment facilities in cities is vital to minimize costs and improve the More
Facility location problems are one of the most important issues for healthcare organizations and centers to achieve social welfare and respond to customer needs. Proper distribution of health and treatment facilities in cities is vital to minimize costs and improve the efficiency of health centers. The main contribution of the current article is dealing with the uncertainty issue in the p-median location-efficient problem. In this article, the p-median location problem along with network data envelopment analysis (Network DEA) is used in parallel mode to calculate the efficiency of health and treatment centers. In this issue, health centers are considered as parallel networks with two departments that operate independently. Due to the precision of the input and output values, triangular fuzzy numbers and the α-level fuzzy method have been used. The primary results that consider the uncertainty provide efficient solution and suggestions for the potential location of health centers in our case study.
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هدف از این مقاله ارائه یک مدل DEA جدید شبکه برای اندازه گیری کارایی زنجیرهای دو تامین کننده و یک تولید کننده تحت مکانیزم سازمان غیرمتمرکز است. در این مکانیزم، هر بخش از زنجیره تامین تحت تصمیم گیری منحصر به فرد خود را با علاقه خود را کنترل می شود. ما پیشنهاد کردیم که در More
هدف از این مقاله ارائه یک مدل DEA جدید شبکه برای اندازه گیری کارایی زنجیرهای دو تامین کننده و یک تولید کننده تحت مکانیزم سازمان غیرمتمرکز است. در این مکانیزم، هر بخش از زنجیره تامین تحت تصمیم گیری منحصر به فرد خود را با علاقه خود را کنترل می شود. ما پیشنهاد کردیم که در مقایسه با مدل CCR برای زنجیره تامین تحت مکانیزم سازمان غیر متمرکز، مناسب نیست که ساختار داخلی را نادیده بگیریم و به عنوان یک جعبه سیاه رفتار کنیم، در حالی که بیش از یک تصمیم گیرنده با منافع متفاوت وجود دارد. علاوه بر این، رابطه بین بهره وری زنجیره تامین و بازده تقسیم بررسی شده است. مثال عددی نشان دهنده کاربرد مدل پیشنهادی است.
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در این مقاله، یک مدل جدید تحلیل پوششی داده های شبکه ای پویا با خروجی های نامطلوب ارائه می گردد. ابتدا، ما از یک رویکرد اصول موضوعه ای در DEA با خروجی نامطلوب استفاده نموده و یک مدل شبکه ای با خروجی های نامطلوب ارائه می نماییم. سپس، رویکرد پیشنهادی را گسترش داده و یک مدل More
در این مقاله، یک مدل جدید تحلیل پوششی داده های شبکه ای پویا با خروجی های نامطلوب ارائه می گردد. ابتدا، ما از یک رویکرد اصول موضوعه ای در DEA با خروجی نامطلوب استفاده نموده و یک مدل شبکه ای با خروجی های نامطلوب ارائه می نماییم. سپس، رویکرد پیشنهادی را گسترش داده و یک مدل با ساختار شبکه ی پویا با خروجی نامطلوب و ورودی ثابت ارائه می نماییم. پس از آن، از این مدل برای ارزیابی عملکرد بیمارستانها در یک مطالعه تجربی برای برآورد کارایی شبکه پویا استفاده می گردد.
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Each steel company buys the raw materials it needs from the manufacturers in question, thus forming supply chains with network properties. Therefore, there is a need to conduct performance research to improve the performance of these chains. In studies, the study of spe More
Each steel company buys the raw materials it needs from the manufacturers in question, thus forming supply chains with network properties. Therefore, there is a need to conduct performance research to improve the performance of these chains. In studies, the study of specific structures in the supply chain has received less attention. In this research, we have tried to examine the network and how to evaluate its performance in the presence of uncontrollable, undesirable factors. For this purpose, network DEA models are proposed that evaluate the performance of the chain in the presence of uncontrollable inputs and outputs, undesirable output even in its internal structure. Then, 11 present steel companies, the corresponding chain of each of which has two stages, were evaluated by the presented models in 1398. The designed model was based on the network Data Envelopment Analysis of tailored the companies under study and their efficiency was calculated. Based on the results, one company under the first stage and one company under the second stage were recognized as efficient, and all companies had a total efficiency of less than one.
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Data envelopment analysis is a non-parametric method for measuring the performance score of a set of units under evaluation. Recently, the application of data envelopment analysis models in networked or multi-stage structures has been considered by researchers. This pap More
Data envelopment analysis is a non-parametric method for measuring the performance score of a set of units under evaluation. Recently, the application of data envelopment analysis models in networked or multi-stage structures has been considered by researchers. This paper seeks to reinforce the first steps taken to develop DEA network models based on asynchronous technology. To this end, it provides a way to consider undesirable outputs in an asynchronous technology. The models presented in this paper, while calculating the overall performance score in a network system, are able to calculate the performance of each step separately in the presence of undesirable factors without any additional calculation and provide it to the system administrators. Also, to show the accuracy of the proposed model compared to the basic CCR model, we conclude the computational accuracy of the model due to the identification of a number of less efficient units than the CCR model. According to the results, despite the fact that some units are considered as efficient, but due to inefficiency in some stages are considered inefficient and only the National Industrial Holding is considered as the only efficient unit due to the fact that it is efficient in both stages.
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