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    Measuring and improving eco-efficiency using Data Envelopment Analysis. A case study of Mahón-Menorca cheese

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    [EN] The concept of eco-efficiency can be defined with the "product value/environmental influence" ratio. Different models have been proposed to measure eco-efficiency. The main difference among them is the weighting system used to aggregate the environmental results. Data envelopment analysis (DEA) permits this aggregation without requiring a subjective judgment about the weights. In this study, we applied a DEA model to Spanish Mahón-Menorca cheese production to determine the most eco-efficient production techniques. To this end, 16 scenarios of Mahón-Menorca cheese production were built regarding technical (degree of automation) and cleaner production criteria. The environmental impacts were assessed by means of life cycle assessment. We carried out an economic assessment by determining the economic value added and the net income for each scenario. The results are referred to as 1 kilogram (kg) cheese ripened over 105 days. Through DEA, an eco-efficiency ratio between 0 and 1 was obtained. Three scenarios were found to be eco-efficient, with a high degree of automation (enclosed vat and molding and demolding machines) and accelerated cheese ripening. We used Monte Carlo simulation to carry out a sensitivity analysis to compare the influence of price changes on the eco-efficiency ratio. The results emphasize the consistency and stability of the eco-efficient scenarios. © 2011 by Yale University.We gratefully acknowledge the financial support from the Spanish Ministry of Education and Science, Project CTM2006-12328/TECNO, and from the Universidad Politecnica de Valencia, Project PAID-05-06-6733. We are also grateful for the help of the Consell Regulador de la Denominacio d'Origen Mahon-Menorca, Alcaidus S. A. T., Cooperativa Insular Ganadera (Coinga), Hort de Sant Patrici, S. L., and Iberlact S. L.Sanjuán Pellicer, MN.; Ribal Sanchis, FJ.; Clemente Polo, G.; Fenollosa Ribera, ML. (2011). Measuring and improving eco-efficiency using Data Envelopment Analysis. A case study of Mahón-Menorca cheese. Journal of Industrial Ecology. 15(4):614-628. https://doi.org/10.1111/j.1530-9290.2011.00347.xS61462815

    Reference Models and Incentive Regulation of Electricity Distribution Networks: An Evaluation of Sweden’s Network Performance Assessment Model (NPAM)

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    The world-wide electricity sector reforms have led to a search for alternative and innovative approaches to regulation to promote efficiency improvement in the natural monopoly electricity networks. A number of countries have used incentive regulation models based on efficiency benchmarking of the electricity network utilities. While most regulators have opted adopted parametric and non-parametric frontier-based methods of benchmarking some have used engineering designed ‘reference firm’ or ‘norm’ models for the purpose. This paper examines the incentive properties and other related aspects of the norm model NPAM used in regulation of distribution networks in Sweden and compares these with those of frontier-based benchmarking methods. We identify a number of important differences between the two approaches to regulation benchmarking that are not readily apparent and discuss their ramifications for the regulatory objectives and process

    Effects of Changes in Public Policy on Efficiency and Productivity of General Hospitals in Vietnam

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    The health sector reform programme which began in Vietnam in 1989 in order to improve the efficiency of the health system has altered the way in which Vietnamese hospitals operate. The programme put the spotlight on input savings. This study aims to examine the relative efficiency of hospitals during the health reform process and assess - by looking at the relative efficiency of hospitals - the effects of the regulatory changes. The study employs the DEA two-stage approach referring to data from 101 general public hospitals over the period 1998-2006. The study revealed that there was evidence of improvement in the productivity of Vietnamese hospitals over the period 1998-2006, with a progress in total factor productivity of 1.4% per year. Furthermore, the differences in hospital efficiency can be attributed to both the regulatory changes and hospital-specific characteristics. The user fees and autonomy measures were found to increase technical efficiency. Provincial hospitals were revealed to be more technically efficient than their central counterparts and hospitals located in the North East, South East and Mekong River Delta regions performed better that hospitals from other regions

    Characterisation of denitrification in the subsurface environment of the Manawatū catchment, New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Earth Science at Massey University, Palmerston North, New Zealand

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    Figures 2.1 & 2.2 have been removed for copyright reasons but may be accessed via their source listed in the References (Rivett et al., 2008, Fig. 2 & Saggar et al., 2013, Fig. 3).A sound understanding of the quantity of nitrate lost from agricultural soils, as well as their transport and transformation in soil-water systems is essential for targeted and effective management and/or mitigation of their impacts on the quality of receiving waters. However, there is currently little known about the occurrence, variability, or factors affecting, nitrate attenuation by subsurface (below the root zone) denitrification in New Zealand, particularly in the Manawatū River catchment. This thesis developed and applied a combination of regional- and local-scale hydrogeochemical surveys and experiments, to gain an insight into the occurrence, variability, and hydrogeological features of subsurface denitrification in the Manawatū River catchment, particularly in the Tararua Groundwater Management Zone (GWMZ). A regional survey and analysis of samples from 56 groundwater wells conducted in the Tararua GWMZ revealed mainly oxic groundwater with low denitrification potential in the southern part of the catchment (Mangatainoka sub-catchment), whereas mainly anoxic/reduced groundwaters with high potential to denitrify in the middle and northern parts (Upper Manawatū sub-catchments). Oxic groundwaters with enriched nitrate concentrations were generally correlated with coarse textured soil types and aquifer materials (e.g., well-drained soil, gravel rock type), allowing faster movement of percolating water and oxygen diffusion from surface to subsurface environments. Local-scale laboratory incubations and in-field, push-pull test techniques were evaluated and optimised to measure and quantify denitrification in unsaturated (vadose) and saturated (shallow groundwater) parts of the subsurface environment. A novel incubation technique using vacuum pouches was found to be more reliable than traditional Erlenmeyer flasks in determining denitrifying enzyme activity (DEA) in subsurface soils (>0.3 m depth) with low denitrification activity. A combination of 75 μg N g-1 dry soil and 400 μg C g-1 dry soil was also found to provide the optimum DEA in subsurface soils. In the evaluation of the push-pull test, denitrification rates estimated using the measurements of denitrification reactant (nitrate) were found to be significantly higher (6 to 60 times) as compared to the rates estimated using the measurements of denitrification product (nitrous oxide). The estimates of denitrification rates also differed depending on whether a zero-order or first-order kinetic model was assumed. However, either a zero-order or a first-order model appears to be valid to estimate the denitrification rate from push-pull test data. The optimised laboratory incubation technique and in-field, push-pull test were applied at four sites with contrasting redox properties; Palmerston North, Pahiatua, Woodville, and Dannevirke. The incubation technique revealed that denitrification potential in terms of DEA is highest in the surface soil and generally decreased with soil depth. The push-pull test measured large denitrification rates of 0.04 to 1.07 mg N L-1 h-1 in the reduced groundwaters at depths of 4.5-7.5 m below ground level at two of the sites (Woodville and Palmerston North), whereas there were no clear indications of denitrification in the oxidised shallow groundwaters at the other two sites (Pahiatua and Dannevirke). This new knowledge, information and techniques advance our scientific capability to assess and map subsurface denitrification potential for targeted and effective land use planning and water quality measures in the Manawatū catchment and other catchments across New Zealand’s agricultural landscapes and worldwide

    The competitiveness of nations and implications for human development

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    This is the post-print version of the final paper published in Socio-Economic Planning Sciences. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2010 Elsevier B.V.Human development should be the ultimate objective of human activity, its aim being healthier, longer, and fuller lives. Thus, if the competitiveness of a nation is properly managed, enhanced human welfare should be the key expected consequence. The research described here explores the relationship between the competitiveness of a nation and its implications for human development. For this purpose, 45 countries were evaluated initially using data envelopment analysis. In this stage, global competitiveness indicators were taken as input variables with human development index indicators as output variables. Subsequently, an artificial neural network analysis was conducted to identify those factors having the greatest impact on efficiency scores

    Efficiency of public and publicly-subsidised high schools in Spain. Evidence from PISA 2006

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    The purpose of this paper is to compare the efficiency of the Spanish public and publicly-subsidised private high schools using Data Envelopment Analysis (DEA) fed by the results provided by a hierarchical linear model (HLM) applied to PISA-2006 (Programme for International Students Assessment) microdata. This study places special emphasis on the estimation of the determinants of school outcomes, the educational production function being estimated through an HLM that takes into account the nested nature of PISA data. Inefficiencies are then measured through the DEA and decomposed into managerial (related to individual performance) and programme (related to structural differences between management models), following Silva Portela and Thanassoulis (2001) approach. Once differences in pupils’ background and individual management inefficiencies have been eliminated, results reveal that Spanish public high schools are more efficient than publicly-subsidised private ones

    Efficiency Measurement in the Local Public Sector: Econometric and Mathematical Programming Frontier Techniques

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    Local government in advanced economies is undergoing a period of rapid reform aimed at enhancing its efficiency and effectiveness. Accordingly, the definition, measurement and improvement of organisational performance is crucial. Despite the importance of efficiency measurement in local government it is only relatively recently that econometric and mathematical frontier techniques have been applied to local public services. This paper attempts to provide a synoptic survey of the comparatively few empirical analyses of efficiency measurement in local government. We examine both the measurement of inefficiency in local public services and the determinants of local public sector efficiency. The implications of efficiency measurement for practitioners in local government are examined by way of conclusion.

    Performance evaluation using bootstrapping DEA techniques: Evidence from industry ratio analysis

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    In Data Envelopment Analysis (DEA) context financial data/ ratios have been used in order to produce a unified measure of performance metric. However, several scholars have indicated that the inclusion of financial ratios create biased efficiency estimates with implications on firms’ and industries’ performance evaluation. There have been several DEA formulations and techniques dealing with this problem including sensitivity analysis, Prior-Ratio-Analysis and DEA/ output–input ratio analysis for the assessment of the efficiency and ranking of the examined units. In addition to these computational approaches this paper in order to overcome these problems applies bootstrap techniques. Moreover it provides an application evaluating the performance of 23 Greek manufacturing sectors with the use of financial data. The results reveal that in the first stage of our sensitivity analysis the efficiencies obtained are biased. However, after applying the bootstrap techniques the sensitivity analysis reveals that the efficiency scores have been significantly improved.Performance measurement; Data Envelopment Analysis; Financial ratios; Bootstrap; Bias correction
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