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1.
针对模糊环境下决策单元的相对有效性评价问题,本文利用α-截集法将三角模糊数型的投入产出值转化为区间数,提出一种改进的区间交叉效率模型。随后,引入前景理论来研究区间交叉效率集结问题,定义区间参考点代替传统的单个参考点,以最大化所有决策单元的前景交叉效率为原则,构建最大化前景交叉效率模型求解集结权重。根据偏好度方法,比较区间交叉效率值。本文方法基于统一的生产前沿面来度量决策单元的效率,保证了不同决策单元之间以及不同α值下的效率可比;定义区间参考点充分考虑了决策者在模糊环境下的心理因素变化,集结决策单元的区间交叉效率值代替综合前景值,以保留尽可能多的决策信息。最后,通过例子验证方法的有效性。  相似文献   

2.
根据样本单元的区间投入、区间产出定义最大样本生产可能集,建立基于最大样本生产可能集的广义超效率区间DEA模型,然后定义了待评价决策单元基于广义超效率区间DEA模型的超效率区间,并讨论了待评价决策单元的有效性,最后通过实例表明了广义超效率区间DEA模型的实用性.  相似文献   

3.
针对投入变量缺失生产服务系统,提出一种基于DEA的相对效率评价方法.由于该系统的投入无法确知,首先需要依据产出对各决策单元(DMU)进行分组,并将其相对效率分解为组内效率与组间效率.对于组内效率,引人虚拟投入变量利用传统超效率DEA模型进行评价.而对于组间效率,则建立扩展的超效率DEA模型.最终以两类效率之积评价所有决策单元之间的相对效率.理论分析表明:投入缺失系统内决策单元有效的充要条件是其组内效率及其所在组的组间效率均有效.文章最后以基金项目评审为例进行实证分析,说明了本方法的合理性与可行性.  相似文献   

4.
数据包络分析(DEA)是一种评价具有多投入、多产出决策单元的相对效率的线性规划方法.在现实世界中,决策单元有时呈现出由多个独立子系统构成的复杂并联网络系统,各子系统的投入/产出之和构成了系统的总投入/产出.目前,用于评价这种具有并联网络生产系统相对效率的模型主要有三种:网络DEA模型、多部门DEA模型和关联DEA模型.现有这些模型的基本特性和相互关系存在着不足,即子系统的效率分解和优化指数不唯一.为解决这一问题,提出了改进的并联DEA模型,并采用加拿大银行系统实例来说明所提出模型的合理性和有效性.  相似文献   

5.
经典的DEA模型视决策单元为黑匣子,不考虑内部结构.实际上,决策单元DMU可能具有各种各样的结构.对DMU进行效率评价时,尽管最初的输入和最终的输出相同,但考虑DMU结构与忽视DMU结构得到的效率不同.基于这样一种思想,提出了一种基于层次系统的DEA模型.  相似文献   

6.
针对DEA交叉效率评价过程中没有考虑自评与互评效率的作用而主观赋予相同权重导致交叉效率评价值不准确的问题.文章基于参数设计的思想,依据试验设计中可控与不可控因素的作用机理区分自评权重和互评权重对所评价决策单元交叉效率的影响与作用,将其界定为可控与不可控因素的管理学属性,明确不同权重作用机理;引入信噪比作为衡量决策单元交叉效率评价时的性能指标,实施DEA交叉效率评价方法的改进,设计出DEA信噪比交叉效率集结方法,从而实现交叉效率的集结方式由单一考虑交叉效率波动的均值转化为综合考虑交叉效率波动情况(均值与方差),交叉效率评价值用信噪比交叉效率替代交叉效率平均值更具有统计学意义并可从管理学角度解释,评价结果也具有更高的可区分性;最后通过算例分析验证了交叉效率评价理论上的必要性和该方法的合理性与可行性,同时发现了交叉效率评价中存在CCR有效DMU序位超出了有效DMU范围现象,建议应实施同质DMU检验和评价值归一化.文章的研究也为提高DEA交叉效率测算的准确性提供一种新思路.  相似文献   

7.
任娟  陈圻 《运筹与管理》2013,22(1):194-200
针对有效决策单元评价和区分的问题,在充分提取决策单元之间相似性和相异性信息基础上,定义了多指标区间交叉效率,进而提出了一种基于投入、产出权重的聚类分析方法,并将其应用于竞争战略识别.实证结果表明,该方法能够区分有效决策单元,综合评价具有统一性和合理性;与同类战略识别方法相比,更具客观性和解释能力,分类效果更好.该方法提供了一种客观的新的竞争战略识别方法,有助于战略有效性的研究.  相似文献   

8.
传统交叉效率方法往往采用相加平均的方式来集结效率,这不仅缺乏足够的理论依据,而且导致大量决策信息的遗失.针对这个问题,文章引入前景理论来研究决策者面临收益和损失时的主观价值感受,并分别在乐观型、中立型和悲观型决策偏好的引导下构建相应的效率集结方法.随后,引入距离熵的概念来衡量不同决策单元视角下评价结果的可靠性,以此修正交叉效率集结结果.该集结方法充分考虑了决策者的主观偏好,并在其引导下最大程度地保留了决策信息,从而获得最符合现实决策需求的效率评价结果.最后,通过案例分析来验证该方法的有效性.  相似文献   

9.
传统交叉效率方法往往采用相加平均的方式来集结效率,这不仅缺乏足够的理论依据,而且导致大量决策信息的遗失.针对这个问题,文章引入前景理论来研究决策者面临收益和损失时的主观价值感受,并分别在乐观型、中立型和悲观型决策偏好的引导下构建相应的效率集结方法.随后,引入距离熵的概念来衡量不同决策单元视角下评价结果的可靠性,以此修正交叉效率集结结果.该集结方法充分考虑了决策者的主观偏好,并在其引导下最大程度地保留了决策信息,从而获得最符合现实决策需求的效率评价结果.最后,通过案例分析来验证该方法的有效性.  相似文献   

10.
数据包络分析已经被广泛应用于研究中国各省市的能源与环境效率.在以前研究文献中,模拟弱可处置性建模时,隐含的假设所有决策单元采用统一均匀的减少系数.但是在实际生产过程中,面对边际减排成本最低的决策单元,减少非期望产出,也通常会带来成本效益,而且决策者也往往更倾向于减少那些带来成本效益更低的决策单元.因此,为解决这一实际问题,引进不同决策单元的非期望产出采用非均匀比例减少的基础上,考虑非能源投入和能源投入的划分,来构建评估中国各个省市能源和环境效率的生产可能集,然后利用改善的DEA模型计算2016年中国其中30个省市的能源与环境效率.结果表明,我国不同区域,相同区域不同省市之间的能源与环境效率都存在着较大差异.  相似文献   

11.
朱运霞  昂胜  杨锋 《运筹与管理》2021,30(4):184-189
在数据包络分析(DEA)中,公共权重模型是决策单元效率评价与排序的常用方法之一。与传统DEA模型相比,公共权重模型用一组公共的投入产出权重评价所有决策单元,评价结果往往更具有区分度且更为客观。本文考虑决策单元对排序位置的满意程度,提出了基于最大化最小满意度和最大化平均满意度两类新的公共权重模型。首先,基于随机多准则可接受度分析(SMAA)方法,计算出每个决策单元处于各个排名位置的可接受度;然后,通过逆权重空间分析,分别求得使最小满意度和平均满意度最大化的一组公共权重;最后,利用所求的公共权重,计算各决策单元的效率值及相应的排序。算例分析验证了本文提出的基于SMAA的公共权重模型用于决策单元效率评价与排序的可行性。  相似文献   

12.
This study addresses the problem of finding the range of efficiency for each Decision Making Unit (DMU) considering uncertain data. Uncertainty in the DMU coefficients in each factor (input or output) is captured through interval coefficients (ie, these are uncertain but bounded). A two-phase additive Data Envelopment Analysis model for performance evaluation is used, which is adapted to include the concept of super-efficiency to provide a robustness analysis of the DMUs in face of uncertain information, assessing whether each DMU is surely efficient, potentially efficient, or surely inefficient for the uncertainty intervals specified. Another contribution is to present how a maximal stability hyper-rectangle can be computed for each DMU such that its efficiency status does not change when the coefficients vary within that interval.  相似文献   

13.
Cross-efficiency evaluation is a commonly used approach for ranking decision-making units (DMUs) in data envelopment analysis (DEA). The weights used in the cross-efficiency evaluation may sometimes differ significantly among the inputs and outputs. This paper proposes some alternative DEA models to minimize the virtual disparity in the cross-efficiency evaluation. The proposed DEA models determine the input and output weights of each DMU in a neutral way without being aggressive or benevolent to the other DMUs. Numerical examples are tested to show the validity and effectiveness of the proposed DEA models and illustrate their significant role in reducing the number of zero weights.  相似文献   

14.
The concept of efficiency in data envelopment analysis (DEA) is defined as weighted sum of outputs/weighted sum of inputs. In order to calculate the maximum efficiency score, each decision making unit (DMU)’s inputs and outputs are assigned to different weights. Hence, the classical DEA allows the weight flexibility. Therefore, even if they are important, the inputs or outputs of some DMUs can be assigned zero (0) weights. Thus, these inputs or outputs are neglected in the evaluation. Also, some DMUs may be defined as efficient even if they are inefficient. This situation leads to unrealistic results. Also to eliminate the problem of weight flexibility, weight restrictions are made in DEA. In our study, we proposed a new model which has not been published in the literature. We describe it as the restricted data envelopment analysis ((ARIII(COR))) model with correlation coefficients. The aim for developing this new model, is to take into account the relations between variables using correlation coefficients. Also, these relations were added as constraints to the CCR and BCC models. For this purpose, the correlation coefficients were used in the restrictions of input–output each one alone and their combination together. Inputs and outputs are related to the degree of correlation between each other in the production. Previous studies did not take into account the relationship between inputs/outputs variables. So, only with expert opinions or an objective method, weight restrictions have been made. In our study, the weights for input and output variables were determined, according to the correlations between input and output variables. The proposed new method is different from other methods in the literature, because the efficiency scores were calculated at the level of correlations between the input and/or output variables.  相似文献   

15.
实际系统评价问题中,输入输出指标之间往往并非独立,而是存在着复杂的影响与反馈关系.传统AHP-DEA模型直接采用层次分析法(AHP)构造约束锥,容易使指标权重产生较大偏差甚至出现错误.通过网络分析法(ANP)确定了权重,反向构造了AHP约束锥,并与DEA模型结合,建立了AHP-DEA模型.同时,开展了逆向物流服务供应商选择应用研究,应用结果表明,基于ANP权重确定的AHP-DEA模型能够有效解决多个决策单元均有效而无法区分优劣的问题.  相似文献   

16.
The slacks-based measure (SBM) can incorporate input and output slacks that would otherwise be neglected in the classical DEA model. In parallel, the super-efficiency model for SBM (S-SBM) has been developed for the purpose of ranking SBM efficient decision-making units (DMUs). When implementing SBM in conjunction with S-SBM, however, several issues can arise. First, unlike the standard super-efficiency model, S-SBM can only solve for super-efficiency scores but not SBM scores. Second, the S-SBM model may result in weakly efficient reference points. Third, the S-SBM and SBM scores for certain DMUs may be discontinuous with a perturbation to their inputs and outputs, making it hard to interpret and justify the scores in applications and the efficiency scores may be sensitive to small changes/errors in data. Due to this discontinuity, the S-SBM model may overestimate the super-efficiency score. This paper extends the existing SBM approaches and develops a joint model (J-SBM) that addresses the above issues; namely, the J-SBM model can (1) simultaneously compute SBM scores for inefficient DMUs and super-efficiency for efficient DMUs, (2) guarantee the reference points generated by the joint model are Pareto-efficient, and (3) the J-SBM scores of a firm are continuous in the input and output space. Interestingly, the radial DEA efficiency and super-efficiency scores for a DMU are continuous in the input–output space. The J-SBM model combines the merits of the radial and SBM models (i.e., continuity and Pareto-efficiency).  相似文献   

17.
In this paper we show that data envelopment analysis (DEA) can be viewed as maximising the average efficiency of the decision-making units (DMUs) in an organisation. Building upon this we present DEA based models for: (a) allocating fixed costs to DMUs and (b) allocating input resources to DMUs. Simultaneous to allocating input resources output targets are also decided for each DMU. Numeric results are presented for a number of example problems taken from the literature.  相似文献   

18.
《Applied Mathematical Modelling》2014,38(7-8):2028-2036
Conventional DEA models assume deterministic, precise and non-negative data for input and output observations. However, real applications may be characterized by observations that are given in form of intervals and include negative numbers. For instance, the consumption of electricity in decentralized energy resources may be either negative or positive, depending on the heat consumption. Likewise, the heat losses in distribution networks may be within a certain range, depending on e.g. external temperature and real-time outtake. Complementing earlier work separately addressing the two problems; interval data and negative data; we propose a comprehensive evaluation process for measuring the relative efficiencies of a set of DMUs in DEA. In our general formulation, the intervals may contain upper or lower bounds with different signs. The proposed method determines upper and lower bounds for the technical efficiency through the limits of the intervals after decomposition. Based on the interval scores, DMUs are then classified into three classes, namely, the strictly efficient, weakly efficient and inefficient. An intuitive ranking approach is presented for the respective classes. The approach is demonstrated through an application to the evaluation of bank branches.  相似文献   

19.
One of the most important information given by data envelopment analysis models is the cost, revenue and profit efficiency of decision making units (DMUs). Cost efficiency is defined as the ratio of minimum costs to current costs, while revenue efficiency is defined as the ratio of maximum revenue to current revenue of the DMU. This paper presents a framework where data envelopment analysis (DEA) is used to measure cost, revenue and profit efficiency with fuzzy data. In such cases, the classical models cannot be used, because input and output data appear in the form of ranges. When the data are fuzzy, the cost, revenue and profit efficiency measures calculated from the data should be uncertain as well. Fuzzy DEA models emerge as another class of DEA models to account for imprecise inputs and outputs for DMUs. Although several approaches for solving fuzzy DEA models have been developed, numerous deficiencies including the α-cut approaches and types of fuzzy numbers must still be improved. This scheme embraces evaluation method based on vector for proposed fuzzy model. This paper proposes generalized cost, revenue and profit efficiency models in fuzzy data envelopment analysis. The practical application of these models is illustrated by a numerical example.  相似文献   

20.
Data envelopment analysis (DEA) is a data-oriented approach for evaluating the performances of a set of peer entities called decision-making units (DMUs), whose performance is determined based on multiple measures. The traditional DEA, which is based on the concept of efficiency frontier (output frontier), determines the best efficiency score that can be assigned to each DMU. Based on these scores, DMUs are classified into DEA-efficient (optimistic efficient) or DEA-non-efficient (optimistic non-efficient) units, and the DEA-efficient DMUs determine the efficiency frontier. There is a comparable approach which uses the concept of inefficiency frontier (input frontier) for determining the worst relative efficiency score that can be assigned to each DMU. DMUs on the inefficiency frontier are specified as DEA-inefficient or pessimistic inefficient, and those that do not lie on the inefficient frontier, are declared to be DEA-non-inefficient or pessimistic non-inefficient. In this paper, we argue that both relative efficiencies should be considered simultaneously, and any approach that considers only one of them will be biased. For measuring the overall performance of the DMUs, we propose to integrate both efficiencies in the form of an interval, and we call the proposed DEA models for efficiency measurement the bounded DEA models. In this way, the efficiency interval provides the decision maker with all the possible values of efficiency, which reflect various perspectives. A numerical example is presented to illustrate the application of the proposed DEA models.  相似文献   

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