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1.
Abstract

Addressing the intersection of two important emerging research areas, re-distributed manufacturing (RDM) and the food-energy-water (FEW) nexus, this work combines insights from engineering, business and policy perspectives and explores opportunities and challenges towards a more localized and sustainable food system. Analysis centred on two specific food products, namely bread and tomato paste reveals that the feasibility and potential of RDM vary with the type of food product and the supply chain (SC) components. Physically, energy efficiency, water consumption and reduction of waste and carbon footprint may be affected by scale and location of production activities and potentials of industrial symbiosis. From the business perspective, novel products, new markets and new business models are expected in order for food RDM to penetrate within the established food industry. Studies on policies, through the lens of public procurement, call for solid evidence of envisioned environmental, social and economic benefits of a more localized food system. An initial integrated framework is proposed for understanding and assessing food RDM and the FEW nexus.  相似文献   

2.
The problem of infeasibility arises in conventional radial super-efficiency data envelopment analysis (DEA) models under variable returns to scale (VRS). To tackle this issue, a Nerlove–Luenberger (N–L) measure of super-efficiency is developed based on a directional distance function. Although this N–L super-efficiency model does not suffer infeasibility problem as in the conventional radial super-efficiency DEA models, it can produce an infeasible solution in two special situations. The current paper proposes to modify the directional distance function by selecting proper feasible reference bundles so that the resulting N–L measure of super-efficiency is always feasible. As a result, our modified VRS super-efficiency model successfully addresses the infeasibility issues occurring either in conventional VRS models or the N–L super-efficiency model. Numerical examples are used to demonstrate our approach and compare results obtained from various super-efficiency measures.  相似文献   

3.
We propose new diversification-consistent DEA models suitable for assessing efficiency of investment opportunities available on financial markets. The formulations based on directional distance measures enable to use several risk measures as inputs and return measures as outputs, which can take both positive and negative values. We show that various models with different strength can be obtained and strongly, semi-strongly or weakly Pareto–Koopmans efficient investment opportunities can be identified. Moreover, the optimal solutions correspond to efficient investment opportunities and can be used by investors to revise the inefficient ones. If we consider discretely distributed returns, we can prove that under proper choice of the inputs (CVaRs) and outputs (expected return), the strongest model is able to identify efficient investment opportunities with respect to the second-order stochastic dominance. Moreover, the model can be formulated as a linear programming problem. In the numerical study, the proposed DEA models are applied to 48 representative industry portfolios from US stock markets.  相似文献   

4.
This paper introduces a new methodology ensuring units invariant slack selection in radial DEA models and incorporating the slacks into an overall efficiency score. The CCR and BCC models are units invariant in their radial component, but not in their slack component, thus changing the units of measurement of one or more variables can change the models' solution. The proposed Full Proportional Slack (FPS) methodology improves the slack selections of the CCR and BCC models by producing slack selections that (a) are units invariant, thus producing fully units invariant models, (b) maximize the relative improvements represented by the slacks, and not their values, and (c) measure the full slacks that need to be removed from their corresponding variables. The FPS methodology is a fully oriented methodology first maximizing the improvements in the variables on the side of the orientation of the model. The Proportional Slack Adjusted (PSA) methodology incorporates the FPS slacks into an overall efficiency score, making it easier to interpret and use the results. The FPS and PSA methodologies are illustrated using an input oriented VRS Loan Quality DEA model with data from the retail branch network of one of Canada's largest banks.  相似文献   

5.
存在第三方回收商的闭环供应链中,研究了制造商规模不经情形下,政府奖惩机制对其合作策略的影响。分别构建了制造商仅与零售商(回收商)合作、制造商与零售商和回收商都合作以及均不合作四种合作策略。研究发现:制造商与零售商或回收商均存在合作动机。但是其合作动机的大小则与制造商规模不经济系数及政府奖惩力度有关。若制造商规模不经济系数较小:当政府奖惩力度较小时,制造商倾向与零售商合作;当政府奖惩力度较大时,制造商更倾向与回收商合作;若制造商规模不经济系数较大,制造商总是倾向与回收商合作。此外,无论制造商与零售商或回收商合作总是有利增加旧产品回收总量。  相似文献   

6.
在基本的SV模型中引入包含丰富日内高频信息的已实现测度,同时考虑其偏差修正以及波动率非对称性与长记忆性,构建了双因子非对称已实现SV(2FARSV)模型.进一步基于连续粒子滤波算法,给出了2FARSV模型参数的极大似然估计方法.蒙特卡罗模拟实验表明,给出的估计方法是有效的.采用上证综合指数和深证成份指数日内高频数据计算已实现波动率(RV)和已实现极差波动率(RRV),对2FARSV模型进行了实证研究.结果表明:RV和RRV都是真实日度波动率的有偏估计(下偏),但RRV相比RV是更有效的波动率估计量;沪深股市具有强的波动率持续性以及显著的波动率非对称性(杠杆效应与规模效应);2FARSV模型相比其它已实现波动率模型具有更好的数据拟合效果,该模型能够充分地捕获沪深股市波动率的动态特征(时变性、聚集性、非对称性与长记忆性).  相似文献   

7.
Abstract

The linear production of consumer goods is characterised by mass manufacture, multinational enterprises and globally dispersed supply chains. Redistributed manufacture (RDM) is an emerging topic, which seeks to enable a transition of the current linear model of production and consumption, by taking advantage of new technologies. This paper aims to explore the challenges, opportunities and further research questions to set a vision of Redistributed manufacturing for the UK’s consumer goods industry. To set this vision, a literature survey was conducted followed by a qualitative enquiry where PESTLE1 aspects of RDM were analysed. This analysis was interpreted through a roadmap. As a result of this roadmap, four RDM characteristics (i.e. customisation, use of digital technologies, local production and the development of new business models) were identified. These characteristics helped to set the future vision of RDM in the UK’s consumer goods sector.  相似文献   

8.
Abstract

This paper extends operations strategy theory on efficiency and flexibility trade-offs to the emergent phenomenon of redistributed manufacturing (RDM). The study adopts a multiple-case design including five small and five large pharmaceutical firms. We propose that organizations can gain the efficiency benefits of centralized manufacturing and the flexibility advantages of RDM by building an ambidexterity capability. To build such a capability, large firms can structurally partition their manufacturing and supply management functions, with one sub-unit managing centralized production and the other RDM. Smaller enterprises can build an ambidexterity capability by creating the right organizational context, where multi-skilled workers switch between efficient and flexible tasks. This paper contributes to theory by explaining the emergence of RDM using an organizational ambidexterity lens, laying the groundwork for new theory development in the field. We provide managers with a practical example of how to build an ambidexterity capability to realize flexibility and efficiency advantages.  相似文献   

9.
Cross efficiency is a concept for solving the problem of incomparability among the efficiencies of a set of decision making units (DMUs) calculated from different weights in data envelopment analysis, and is helpful for ranking. Conventional cross efficiency is a radial measure, and the radial measure has some weaknesses. First, it is not able to provide appropriate efficiency scores for weakly efficient DMUs. Second, the efficiencies measured from the input and output sides under variable returns to scale are different which may cause difficulties in subsequent analyses. Third, negative values may appear when the efficiency is measured from the input side. To solve these problems, this paper proposes a slacks-based measure to calculate efficiency. The basic idea is the same as that of the radial measure using the frontier corresponding to a DMU to measure the efficiency of all DMUs, except that the efficiency measure is slacks-based instead of radial. Due to the nature of the slacks-based efficiency measure, the problems caused by weak efficiency and difference in input and output radial measures do not exist. More importantly, negative efficiencies are not produced. The proposed method is applied to a real case involving the selection of the most efficient robot to use for production. The results help identify the top-ranked robot.  相似文献   

10.
The Bounded Adjusted Measure (BAM), initially defined for the additive model, which is a variable returns to scale (VRS) model, was extended to the constant returns to scale (CRS) case [7]. The added range-bounds, which maintain unaltered the production possibility set (PPS) under VRS, showed an influential effect under CRS, reducing the corresponding PPS, as well as a negative effect, excluding some of the original CRS projections. Here we propose an enhanced extension that, by considering a different set of less restrictive bounds, eliminates the negative effect. Moreover, we customize this new extension for the family of partially bounded CRS additive models, i.e., models where at least one variable is naturally bounded from below, if it is an input, or from above, if it is an output.  相似文献   

11.
R&D (Research and Development) activities represent the basic core of corporate science and technology activities, and play a crucial role in enhancing the ability of companies to achieve rapid and sustainable growth. In recent years, the total R&D investments in China have increased significantly and the proportion of the industrial investments in R&D activities relative to national R&D investments has increased rapidly. In order to investigate the effectiveness of these R&D investments, we utilize Data Envelopment Analysis (DEA) models to evaluate the relative efficiencies of 30 regional R&D investments using the First Official China Economic Census Data in 2004. Our investigation and study indicate the following: (1) Only six provinces are global technical efficient and the performance of regional R&D investments in China needs to improve dramatically. (2) Increasing returns to scale have not yet occurred in any province. Constant returns to scale have prevailed in most provinces in the Western region, and decreasing returns to scale have prevailed in most provinces in the Eastern and Central regions. (3) There are no direct relationships between global technical efficiency and the amount of R&D investment. The Western region has the highest average radial efficiency score, followed by the Eastern region, and then by the Central region. (4) The Eastern region has advantages in local technical efficiency, the Western region has advantages in scale efficiency, while the Central region has neither technical efficiency advantages nor scale efficiency advantages. Suggestions are proposed to improve efficiencies of regional R&D investments.  相似文献   

12.
具有独立子系统的DEA模型及其应用   总被引:7,自引:0,他引:7  
考虑到现有的DEA模型基本都是针对单系统的,而仅有的多系统模型[10]也是在假设决策单元相互独立并且不存在规模收益的条件下给出的,本文首先建立了3个评价具有独立子系统的决策单元相对有效性的DEA模型,即假设存在规模收益的模型(1),允许存在组内合作的模型(2),组内与组间都可以进行合作的模型(3),并通过分析3个模型之间的关系得到了决策单元通过组内或者组间合作带来的收益,同时证明了模型的一些性质以及决策单元相对有效与子系统相对有效之间的关系,进而应用这3个模型对1997年我国制造业的东、西、中三个区域的域内以及域间合作问题作了研究.结果表明:本文建立的模型不仅可以得到不同省市制造业的整体效率,而且还可以得到各省市制造业的不同行业的效率以及通过域内或域间合作带来的收益,从而得到运作和管理效率低下的根本原因.  相似文献   

13.
《Omega》2004,32(3):213-219
Super-efficiency data envelopment analysis (DEA) model can be used in ranking the performance of efficient decision making units (DMUs). Because of the infeasibility problem associated with the super-efficiency DEA model, ranking has been restricted to the model where constant returns to scale and proportional changes in all inputs or all outputs are assumed. In fact, when super-efficiency is used as an efficiency stability measure, infeasibility means the highest super-efficiency. However, if super-efficiency is interpreted as input saving or output surplus achieved by a specific efficient DMU, infeasibility does not necessarily mean the highest super-efficiency. In order to obtain a complete ranking of efficient DMUs when the two assumptions are relaxed, a modified super-efficiency DEA model is proposed to overcome the infeasibility problem and to correctly capture the super-efficiency represented by the input saving or the output surplus. The current paper suggests using both input- and output-oriented super-efficiency models to characterize the super-efficiency when infeasibility occurs. As a result, we can rank the efficient DMUs if infeasibility occurs. The approach is applied to 20 largest Japanese companies and 15 US cities, respectively.  相似文献   

14.
The Italian gas distribution industry presents a high degree of fragmentation. However, the tendency between 1970 and 1998 was a concentration process. Available evidence supports the thesis that local distributors have undertaken a process of scale enlargement. This raises the question of characteristics of returns to scale for such operators as well as the optimal scale at which they should operate. Returns to scale are analysed by data envelopment analysis (DEA) methodology. The results show that the output space in which DMUs attain a high level of scale efficiency is widespread, thus indicating an unexpected return to scale characterisation. Technology shows increasing returns only for the smallest units, but such an effect is rapidly exhausted in favour of a regime of constant returns to scale. The main managerial conclusion is that an improvement of productivity may be reached via an intensification of the merging process involving local distributors operating at a small scale. Moreover, the concentration process appears as an “attainable” objective since the critical dimension, which permits the exploitation of positive returns to scale, is quite small.  相似文献   

15.
In this paper the efficiency assessment of general networks of processes that produce both desirable and undesirable outputs is addressed. This problem arises in many contexts (e.g. transportation, energy generation, etc.). A general networks slacks-based inefficiency (GNSBI) measure can be computed using a simple linear program that takes into account the weak disposability of the bad outputs. The slacks-based inefficiency (SBI) of each process is also calculated. Target values for all inputs, outputs (both desirable and undesirable) and even intermediate products are also provided. The proposed approach is rather general and can accommodate many different network topologies and returns to scale assumptions. Two applications to the banking sector are presented: one to assess banks efficiencies and another to assess bank branches.  相似文献   

16.
本文对Van der Weide(2002)的广义正交GARCH模型进行扩展,提出反映金融资产收益波动性特征,具有"杠杆效应"的广义正交GARCH模型。由于这种扩展的广义正交GARCH模型在高维数据中面临参数估计困难,本文从交互信息理论视角研究模型的参数估计问题,在理论上证明基于交互信息最小化的多元GARCH模型参数估计与基于极大似然函数参数估计的联系和区别,并在提出的扩展广义正交GARCH模型框架下,采用不同的统计技术实现基于交互信息最小化的参数估计方法,避免了传统极大似然函数估计需要事先正确指定标准化残差概率密度函数和高维运算困难,计算效率较高,使多元GARCH模型在高维数据中可以应用。最后,根据全球主要金融市场的15种股票指数数据,通过实证研究对建立的扩展广义正交GARCH模型及其参数估计方法有效性进行评价与检验。实证研究表明了本文提出的扩展广义正交GARCH模型与参数估计方法的优势。  相似文献   

17.
This article tests several nonparametric DEA models for their ability to accurately decompose CO2 emissions change using a Malmquist styled decomposition framework. This production oriented activity analysis involves panel data and two data sets from the literature for comparison. A new Latent Variable radial input-oriented technology is introduced that is closely associated with a Koopmans Efficient Slacks Based Model. The Latent Variable technology simultaneously reduces inputs and undesirable outputs in a single Multiple Objective Linear Program. This production theoretic methodology is adapted to preserve both scale efficiency and causality within the envelopment framework. Finally, the application studies demonstrate the internal consistency of the Latent Variable reduction coefficients, which overturns previous results and paves the way for further research into undesirable externalities.  相似文献   

18.
运用SBM(slack-based measure)方向性距离函数分别计算了赔付率约束下的2006-2016年中国境内的财产保险公司、人身保险公司的经营无效率值,并对无效率值的来源进行分解。在此基础上运用Luenberger生产率指数计算出全要素生产率及其分解项,对中资、外资保险公司的经营效率、全要素生产率及其分解项进行了对比分析。结果表明:财险业的中资大型公司经营效率最高,人身险业的中资公司经营效率明显高于外资公司;投资收益无效率是造成中小型人身险公司和中小型财产险公司无效率的最主要原因;财险业大型公司的全要素生产率低于中小型公司,而人身险业外资公司的全要素生产率明显高于中资公司。  相似文献   

19.
Data envelopment analysis (DEA) can be interpreted as a natural generalization of elemental practices for efficiency and performance evaluation used in diverse areas, some of which have evolved independently of each other and of the traditional efficiency framework of Charnes et al. [Measuring the efficiency of decision making units. European Journal of Operational Research 1978;2(6):429–44]. The paper aims to show that some standard “real-world” procedures employed by practitioners in the fields of retailing, finance, and social science can be interpreted as unconscious applications of DEA, and that such analyses could be enhanced by the explicit use of DEA. A supplementary aim is to demonstrate that DEA can be derived from concrete examples and first principles. The choice of the examples covers the two typical returns to scale environments of constant returns to scale (CRS) and variable returns to scale (VRS). Motivating and deriving DEA as a generalization of established performance evaluation practices will help to explain and disseminate this methodology to practitioners and to those who find their methods familiar.  相似文献   

20.
资源在经济发展中的地位变得越来越重要,本文针对资源分配中存在的某些影响因素是随机的,提出利用随机DEA方法,从三方面综合分析研究资源分配问题,即从生产效率、投入产出弹性和生产潜能。提出并建立了新的随机加权交叉效率计算模型,建立了潜在生产能力模型,给出了规模回报计算公式。综合三个影响因素,建立了新的资源分配权重计算模型。经算例验证,其计算结果令人满意。  相似文献   

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