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1.
Many companies are beginning to change the way they develop products due to increasing awareness of sustainable development. Designers, who play a key role in product development, are being asked to incorporate environmental criteria into the design process. The need for analytically based conceptual design methods for integrated life-cycle assessment (LCA) has motivated the development of an approximate life-cycle assessment concept based upon learning algorithms. Although preliminary tests on general approximate models showed promise, it was observed that grouping products to create specialized learning surrogate LCA models for different classes of products might further improve results. This paper presents work to develop an automated classification system to support the specialization of surrogate LCA models for different groups of products. Hierarchical clustering is used to guide a systematic identification of product groups based upon environmental categories. These groupings are then used to create automated classification schemes using the C4.5 decision tree algorithm. Although further data are needed to induce good generalization performance, resulting product classification systems are considered to be a viable approach to support specialized learning surrogate LCA models for different classes of products.  相似文献   

2.
Dynamic environmental performance analysis: A Malmquist index approach   总被引:8,自引:0,他引:8  
This article presents a general framework for dynamic environmental performance analysis by generalizing the approach proposed by Kuosmanen and Kortelainen [Kuosmanen, T., Kortelainen, M., 2005. Measuring Eco-Efficiency of Production with Data Envelopment Analysis. Journal of Industrial Ecology 9(4), 59-72.] from a static to a dynamic setting. For this purpose we construct an environmental performance index (EPI) by applying frontier efficiency techniques and a Malmquist index approach. Compared to other dynamic environmental productivity and efficiency analysis approaches based on these methods, our approach builds on the standard definition of eco-efficiency as it is presented in the ecological economics literature. Recognizing the importance to analyze the sources of environmental performance changes, we show how changes in overall environmental performance can be decomposed into changes in relative eco-efficiency and shifts in environmental technology, respectively. We apply the presented technique at the macro level to dynamic environmental performance analysis of 20 member states of the European Union in 1990-2003. According to the results, environmental technical change mostly explains the improvement in overall environmental performance, while relative eco-efficiency change has been minor for most countries during the sample period.  相似文献   

3.
We analyze the use of life cycle assessment (LCA) as a regulatory tool using biofuel regulations as an illustrative example. A regulatory context calls for a consequential LCA (CLCA) of a policy as opposed to an attributional LCA (ALCA) of a product. In performing CLCA, issues of scale, price effects, technology and policy in the counterfactual state of the world, strategic behavior, policy horizon etc. need consideration. This appears to increase both uncertainty in estimates and the cost of performing LCA. We suggest heuristics for determining vulnerability to harmful indirect effects at an early stage in the policy process and discuss alternative policies to limit harmful indirect effects without engaging in the full effort of computation and selection of a central estimate for uncertain outcomes.  相似文献   

4.
We consider carefully the evidence from traded prices (as proxied by unit values) concerning the transmission of the effects of globalisation to domestic labour markets. Using standard index number techniques we decompose changes in sectoral import and export unit values into movements due to changes in pure prices of the initial bundle of goods imported or exported and changes due to upgrading of that bundle. Looking at the imports of selected European countries of textiles, clothing and footwear relative to engineering products we find evidence of strongly falling pure prices of the unskilled intensive products relative to the skilled products in the 1980s. This reinforces the view that import prices can capture the impact of globalisation in terms of falling relative prices for products produced with the intensive use of unskilled labour. However, the trends are not common across all the unskilled sectors; footwear is clearly an exception. In the absence of detailed domestic data, we look for reactions by domestic firms to increased import competition in movements in the price and composition of exports. We find evidence of stiff price competition from imports being associated with similar movements in export prices and no support for the view that import competition from low–wage countries has led to upgrading of the quality of exports.  相似文献   

5.
In recent years there has been a tremendous growth in readily available news related to traded assets in international financial markets. This financial news is now available through real-time online sources such as Internet news and social media sources. The increase in the availability of financial news and investor’s ease of access to it has a potentially significant impact on market stock price movement as these news items are swiftly transformed into investors sentiment which in turn drives prices. In this study, we use the Thomson Reuters News Analytics (TRNA) data set to construct a series of daily sentiment scores for Dow Jones Industrial Average (DJIA) stock index constituents. We use these daily DJIA market sentiment scores to study the influence of financial news sentiment scores on the stock returns of these constituents using a multi-factor model. We augment the Fama–French three-factor model with the day’s sentiment score along with lagged scores to evaluate the additional effects of financial news sentiment on stock prices in the context of this model using Ordinary Least Square (OLS) and Quantile Regression (QR) to analyse the effect around the tail of the return distribution. We also conduct the analysis using the seven-day simple moving average (SMA) of the scores to account for news released on non-trading days. Our results suggest that even when market factors are taken into account, sentiment scores have a significant effect on Dow Jones constituent returns and that lagged daily sentiment scores are often significant, suggesting that information compounded in these scores is not immediately reflected in security prices and related return series. The results also indicate that the SMA measure does not have a significant effect on the returns. The analysis using Quantile Regression provides evidence that the news has more impact on left tail compared to the right tail of the returns.  相似文献   

6.
刘洋  杨秋生 《技术经济》2019,35(10):124
城市绿地是重要的绿色基础设施。城市绿地要实现设计目标,保持长久的景观效果离不开持续不断地养护管理,同时管养工作又会带来物资消耗和废弃物排放,对环境造成负面影响。基于生命周期评价方法(LCA),以资源能源消耗和气候变暖潜值作为对环境影响的主要因子,将城市绿地划分为乔木、灌木、地被和草坪层,建立了管养对环境影响的量化模型。以郑州市郑东新区绿地为研究对象,选取34个植物群落(20m×20m)为样本进行了验证,计算得到各植物层管养资源能源消耗和气候变暖潜值特征量以及管养工作标准化加权环境影响指数。结果表明,乔木的管养环境影响指数最低,比群落均值低32%;施肥和垃圾清运是环境影响的主要因素,占群落管养环境影响指数均值的75%以上;与农林业相比,城市绿地管养环境影响指数处中低水平,但资源能源消耗因子的影响指数偏高。基于LCA方法的研究结果可以为城市绿地设计和精细化管理提供量化参考。  相似文献   

7.
The integration of European services markets and the implementation of associated European Union directives open up formerly closed national markets to competition from the Single Market. The purpose of this study is to measure the effects of liberalization on technical efficiency and the productivity development of the insurance industry. As an example we construct efficiency frontiers for the years 1992 through 1999 for the Austrian insurance industry using Data Envelopment Analysis. We use the resulting efficiency scores also to construct a Malmquist productivity index for the transition period. In search for effects from the Single Market, returns to scale, economies of diversification, and distribution channels we relate efficiency and productivity measures to several firm specific characteristics. For this purpose we use unbalanced and balanced panels of individual firm data.All correspondence to Thomas Url. The authors gratefully acknowledge valuable comments from David Cummins, Finn Forsund, Shawna Grosskopf, Michael Theil, seminar participants at the University of Vienna, the University of Business Administration Vienna, the Austrian Institute of Economic Research, the Austrian Insurance Association, and the SOR-Conference Jena, the EOR Conference Brussels, the 25th EGRIE Conference Vienna, and two anonymous referees. Ursula Glavninger provided valuable research assistance.  相似文献   

8.
基于能值分析的土地可持续利用态势研究   总被引:19,自引:0,他引:19  
李双成  蔡运龙 《经济地理》2002,22(3):346-350
本文应用能值分析的理论和方法,构建了基于能值的标定土地可持续利用态势的若干指数,如土地利用总能值投入产出比,土地利用工业能能值投入产出比,土地利用环境负载指数以及土地可持续利用指数。作为案例研究,作者利用上述指数对1978-1999年中车农业土地的可持续性进行判定。结果表明,尽管粮食产量或农业产值等经济指标为土地利用总能值投入产出比和工业能能值投入产出指数前期剧烈下降,后期趋于平缓;土地利用环境负载指数持续上升的态势说明,中国农用土地的环境压力逐渐增大,土地可持续利用指数在前期呈现上升趋势,至1985的达到最高,此后呈持续下降态势,近年趋于稳定。这表明,由过度使用化石能量引起的环境负面效应对农用土地生态系统的压力不断增大,若不遏制这种发展势头,中国农用土地生态系统的可持续性将得不到延存。  相似文献   

9.
This paper considers the application of semiparametric methods to estimate propensity scores or probabilities of program participation, which are central to certain program evaluation methods. To evaluate the practical benefits, we first conduct a Monte Carlo study. Second, we use data from the NSW experiment, CPS, and PSID. We compare treatment effect and evaluation bias estimates using propensity scores estimated from parametric logit, semiparametric single index, and semiparametric binary quantile regression models. Our results suggest that it is important to account for very general forms of heterogeneity in (semiparametric) estimation of the propensity score, particularly when the treatment effects vary in an unsystematic manner with the true propensity score.  相似文献   

10.
Protecting human health is a primary goal of environmental policy and economic evaluation of health can help policy-makers judge the relative worth of alternative actions. Economists use two distinct approaches in normatively evaluating health. Whereas environmental economists use benefit-cost analysis supported by monetary valuation in terms of willingness-to-pay, health economists evaluate interventions based on cost-effectiveness or cost-utility analysis (CEA), using quality-adjusted life-years (QALY) or similar indexes. This paper provides background on the controversy about the relative merits of these approaches and introduces the remaining papers in the special issue. These papers (with one exception) were presented at a conference sponsored by the Department of Economics at the University of Central Florida with support from the US Environmental Protection Agency. Although CEA might not lead to substantially different implications for environmental policy than benefit-cost analysis, and QALY may provide a benefit transfer tool to fill gaps in the morbidity valuation literature, the papers in this issue raise serious concerns about the suitability of QALY-based CEA for environmental regulatory analysis. QALY does not in general appropriately represent individual preferences for health and CEA is neither independent of income distribution nor adequate to assess efficiency.  相似文献   

11.
Ecological footprint accounting in the life cycle assessment of products   总被引:2,自引:0,他引:2  
We present and discuss ecological footprint (EF) calculations for a large number of products and services consumed in the western economy. Product-specific EFs were calculated from consistent and quality-controlled life cycle information of 2630 products and services, including energy, materials, transport, waste treatment and infrastructural processes. We formed 19 homogeneous product/process subgroups for further analysis, containing in total 1549 processes. Per group, the average contribution of two types of land occupation (direct and energy related) to the total EF was derived. It was found that the ecological footprint of the majority of products is dominated by the consumption of non-renewable energy. Notable exceptions are the EFs of biomass energy, hydro energy, paper and cardboard, and agricultural products with a relatively high contribution of direct land occupation. We also compared the ecological footprint results with the results of a commonly used life cycle impact assessment method, the Ecoindicator 99 (EI). It was found that the majority of the products have an EF/EI ratio of around 30 m2-eq. yr/ecopoint ± a factor of 5. The typical ratio reduces to 25 m2 yr/ecopoints by excluding the arbitrary EF for nuclear energy demand. The relatively small variation of this ratio implies that the use of land and use of fossil fuels are important drivers of overall environmental impact. Ecological footprints may therefore serve as a screening indicator for environmental performance. However, our results also show that the usefulness of EF as a stand-alone indicator for environmental impact is limited for product life cycles with relative high mineral consumption and process-specific metal and dust emissions. For these products the EF/EI ratio can substantially deviate from the average value. Finally, we suggest that the ecological footprint product data provided in this paper can be used to improve the footprint estimates of production, import and export of products on a national scale and footprint estimates of various lifestyles.  相似文献   

12.
In the past decade, numerous indicators and indicator sets for sustainable agriculture and sustainable land management have been proposed. In addition to their interest in comparing different management systems on an indicator by indicator basis, land managers are often interested in comparing individual indicators against a threshold, or, in order to study trade-offs, against each other. To this end it is necessary to (1) transform the original indicators into a comparable format, and (2) score these transformed indicators against a sustainability function.This paper introduces an evaluation method for land-use-related impact indicators, which was designed to accomplish these tasks. It is the second of a series of two papers, and as such it links into a larger framework for sustainability assessment of land use systems.The evaluation scheme introduced here comprises (1) a standardisation procedure, which aims at making different indicators comparable. In this procedure indicators are first normalised, by referencing them to the total impact they contribute towards, and then they are corrected by a factor describing the severity of this total impact in terms of exceeding a threshold. The procedure borrows conceptually from Life Cycle Assessment (LCA) Impact Analysis methodology; (2) a valuation procedure, which judges the individual standardised indicators with regard to sustainability.This methodology is then tested on an indicator set for the environmental impact of a spinach production system in Northwest Germany. The method highlights mineral resource consumption, greenhouse gas emission, eutrophication and impacts on soil quality as the most important environmental effects of the studied system.We then explore the effect of introducing weighting factors, reflecting the differing societal perception of diverse environmental issues. Two different sets of weighting factors are used. The influence of weighting is, however, small compared to that of the standardisation procedure introduced earlier.Finally, we explore the propagation of uncertainty (defined as a variable's 95% confidence limits) throughout the standardisation procedure using a stochastic simulation approach. The uncertainty of the analysed standardised indicator was higher than that of the non-standardised indicators by a factor of 2.0 to 2.5.  相似文献   

13.
The aim of this paper is to examine the effectiveness of the first European Pollution Emissions Register (EPER), a regulatory instrument based on the publication of the environmental performance of firms exceeding specified pollution limits. The Multivariate Regression Model (MVRM) is applied to capture the disciplinary effect of the EPER. So, we first perform an analysis to determine whether the publication of the EPER has a negative effect on the market value of the listed firms. Secondly, we consider the possibility of the publication of the EPER affecting the market value of firms which could be included in the EPER but are not because their emissions do not exceed the specified pollution limits. Finally, we prepare an index to compare the environmental results of the firms and analyse whether the consequences of publishing the EPER are worse for firms with high relative pollution records.  相似文献   

14.
Monitoring of the environmental impacts of consumption is necessary for the evaluation of current performance and to support the understanding of how initiatives for change can be implemented. We discuss design issues and methodology for an Environmentally Sensitive Shopper (ESS) index to measure the environmental sustainability of food consumption at the household level. The ESS index is based on revealed consumer preferences and uses scanner data provided by the largest UK food retailer. As a pilot illustration of the methodology, we use the index to identify environmentally critical periods during the calendar year.  相似文献   

15.
Application of input-output analysis to ecological footprints (EFs) is shifting from an ex-post static calculation toward an ex-ante scenario analysis for enhancing the policy relevance of EF analysis. This change in application prompts two issues requiring careful examination: (1) what is measured by Leontief inverses or extended environmental Leontief inverses, and (2) whether a sector's land multiplier (or compositions of land multiplier) can appropriately reflect the effect of delivering one unit of the sector's output to final demand on the required area(s) of production lands used by the sector itself and by other producing sectors whose products are contributed directly and indirectly to its production. The underlying message of these two questions is whether the assumed linear marginal relationship between a sector's output and its intermediate inputs (input-output coefficients)—a critical assumption made by W. Leontief to transform a transactions table from an accounting framework into the input-output model—can be extended to assume that the marginal relationship between a sector's output and the area of production land it uses for generating output is fixed (land-output marginal coefficient equal to average coefficient). By reviewing the literature on input-output analysis and its application to environmental issues and by theoretically and empirically examining the relation between sector output and land appropriation, this study advises against the use of land multipliers or their compositions in the EF scenario analysis.To apply the input-output model to EF scenario analysis for enhancing policy relevance with due attention to the relationship between sector output and land appropriation, this study suggests a two-stage EF calculation procedure. In the first stage, the input-output application estimates only the required raw materials (or generated pollutants) for meeting a given consumption pattern, which is the objective of environmental input-output analysis; in the second stage, the estimated amount of raw materials or pollutants is converted into land/water area, and a choice of conversion methods is suggested according to the research questions and the availability of conversion methods and required data.  相似文献   

16.
Eco-labels are essential for informing consumers about products’ environmental characteristics. However, the many different labels consumers encounter can be confusing, which makes assessing environmental quality associated with each label difficult. How does consumer misperception of competing eco-labels affect market structure and welfare? This article provides theoretical insight into this issue by using a double-differentiation model in which three products compete: an unlabeled product and two distinctly eco-labeled products, one with a medium and one with a high level of environmental quality. The study investigates the effects of consumers’ imperfect information when they perceive all eco-labels as a sign of the same high environmental quality and consider each label as a unique product. This misperception can weaken the firm that provides the greenest product, though paradoxically this situation is not always detrimental to social welfare. However, depending on the certifying organizations, consumer misperception can induce firms to use a greenwashing strategy and encourage nongovernmental organizations and regulators to introduce less stringent standards.  相似文献   

17.
The identification of the market potentials of organic products is important in the drive towards a sustainable agricultural development in sub-Saharan Africa (SSA). However, available evidence shows that valuing attributes of credence goods (such as organic products) while using stated preference methods faces additional obstacles compared to other normal goods. In this study, we examine consumers’ preferences and willingness-to-pay (WTP) for health and environmental attributes of organic products in Nigeria. We employ an approach that allows us to adequately capture the value of organic products by linking part of the heterogeneity across respondents to differences in scale, while making use of indicators of survey engagement, without risks of endogeneity bias and measurement error that arise from the deterministic methods. The empirical results show that market for organic products exists in Nigeria, with reduction in pesticide residues attribute attracting the highest value, followed by the certification programme. Furthermore, we observe that increases in the latent engagement variable lead to a greater probability of agreement with statements relating to survey understanding and realism, and hence more substantive output.  相似文献   

18.
This article features an analysis of the relationship between the DOW JONES Industrial Average (DJIA) Index and a sentiment news series using daily data obtained from the Thomson Reuters News Analytics (TRNA) provided by SIRCA (The Securities Industry Research Centre of the Asia Pacific). The recent growth in the availability of on-line financial news sources, such as internet news and social media sources provides instantaneous access to financial news. Various commercial agencies have started developing their own filtered financial news feeds which are used by investors and traders to support their algorithmic trading strategies. TRNA is one such data set. In this study, we use the TRNA data set to construct a series of daily sentiment scores for DJIA stock index component companies. We use these daily DJIA market sentiment scores to study the relationship between financial news sentiment scores and the stock prices of these companies using entropy measures. The entropy and mutual information (MI) statistics permit an analysis of the amount of information within the sentiment series, its relationship to the DJIA and an indication of how the relationship changes over time.  相似文献   

19.
An Econometric Analysis of Global Waste Paper Recovery and Utilization   总被引:2,自引:0,他引:2  
The main purpose of this paper is to provide aneconometric analysis of the most importantdeterminants of inter-country differences inwaste paper recovery and utilization rates. Byemploying pooled time series and cross-sectiondata over 49 countries worldwide and sevenyears, the paper concludes that relative wastepaper recovery and use depend largely onlong-standing economic factors such aspopulation intensity and competitiveness in theworld market for paper and board products. Wealso find evidence that supports the conjecturethat rich countries tend to recover relativelymore waste paper than is the case in low-incomecountries, reflecting the higher demand forwaste management and environmental policies inmore developed economies. As recovery andutilization rates are determined by economicand demographic characteristics the degree ofpolicy flexibility in affecting these rates maybe limited. In particular, an ambitiousutilization rate target may be very costly toenforce as it can conflict with existing tradepatterns of paper and board products as well aswith other environmental goals. Additionalpolicy targets may therefore be desirable,especially since paper recycling is motivatedprimarily by environmental concerns and seldomis a benign activity in itself.  相似文献   

20.
A nonhypothetical second-price Vickrey auction was conducted to elicit consumer preferences and willingness-to-pay (WTP) for vegetable attributes, including production technique, origin, taste and health benefits. Using a latent class analysis (LCA) we segmented participants based on health-driven motivations, WTP estimates and socio-economic characteristics. Two latent classes were found and characterized as: ‘Health Conscious’ and ‘Health Redeemers’. In particular, the ‘Health Conscious’ consumers presented healthy lifestyle habits, expressed price premiums for domestic and local-specialty food products after a blind tasting treatment, but they did not have price premiums for health benefits of the products. On the contrary, the ‘Health Redeemers’ presented unhealthy lifestyles but they were willing to pay more for healthy food products, perhaps in an attempt to make up for their unhealthy habits.  相似文献   

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