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971.
In the framework of the EU-funded research project ALARM (Assessing LArge-scale environmental Risks with tested Methods), an original method combining the DPSIR (driving forces–pressures–state–impacts–responses) framework and an analysis based on the distinction between the four spheres of sustainability (environmental, economic, social and political) has been developed. This paper presents the application of this method, called “the tetrahedral DPSIR” for the identification and analysis of driving forces of environmental chemicals risks for biodiversity, in Europe. The purpose of this methodology is to help reduce the pressures on biodiversity through modifying the driving forces behind them by offering scientific advice to policy makers. We frame our analysis in the context of the current policy, namely the implementation of REACH (Regulation on the Registration, Evaluation, and Authorization of CHemicals). 相似文献
972.
In search of stars: Network formation among heterogeneous agents 总被引:2,自引:0,他引:2
This paper reports results from a laboratory experiment on network formation among heterogeneous agents. The experimental design extends the Bala–Goyal [Bala, V., Goyal, S., 2000. A non-cooperative model of network formation, Econometrica 68, 1131–1230] model of network formation with decay and two-way flow of benefits by introducing agents with lower linking costs or higher benefits to others. Furthermore, agents' types may be common knowledge or private information. In all treatments, the (efficient) equilibrium network has a “star” structure. While equilibrium predictions fail completely with homogeneous agents, star networks frequently occur with heterogeneous agents. Stars are not born but rather develop: with a high-value agent, the network's centrality, stability, and efficiency all increase over time. A structural econometric model based on best response dynamics and other-regarding preferences is used to analyze individual linking behavior. Maximum-likelihood estimates of the underlying structural parameters, obtained by pooling data from several treatments, allow us to explain the main treatment effects. 相似文献
973.
Fu-Sheng Tsai Author Vitae Linda H.Y. Hsieh Author Vitae Author Vitae Julia L. Lin Author Vitae 《Technological Forecasting and Social Change》2009,76(5):629-643
Incubation has already proven to be of great value in promoting small and medium enterprise (SME) entrepreneurship activities and technological development in developed and developing countries. Incubation not only provides a diversified and integrated service for entrepreneurial ventures but also contributes upward to regional and national innovation and economic growth. Building upon the logic of co-evolution theory, this paper argues that incubation acts at the meso-level as a critical interface between macro-innovation systems and micro-business ventures. These multi-directional coupling elements in innovation ecology co-evolve to achieve collective interests and excellence, which in turn may stimulate technological development and social change. Important processes/mechanisms, including a policy kit and action, strategic networking, supportive associations, knowledge and intellectual capital management, among others, are discussed. Drawing on the national innovation system (NIS) and business incubation (BI) experience in Taiwan, we discuss the future prospects of incubation and innovation policies, including industrializing and globalizing incubation activities and virtual business incubation. 相似文献
974.
Agricultural impacts on water quality and implications for virtual water trading decisions 总被引:2,自引:0,他引:2
Research on the flow of virtual water associated with agricultural crop production and trade has focussed almost entirely on water quantity. It is pertinent to consider and quantify the opportunity costs in terms of reduced water quality associated with crop production. This paper investigates the impacts of water quality on virtual water trading by creating a proxy for water quality impacts by calculating the amount of water required to dilute nonpoint-source agrochemical inputs to relevant water quality guideline values. The quantity of water required for dilution of five agrochemicals (two nutrients; nitrogen and phosphorus and three insecticides; azinphos-methyl, chlorpyrifos and endosulfan) was estimated for five crops in South Africa (maize, wheat, sugar cane, citrus and cotton) and compared to consumption of irrigation water (blue water) and rainfall (green water) for the same crops. Results indicate that the volume of water required for dilution is similar to the total sum of green and blue water required for crop production, but significantly greater than blue water use (irrigation use). For all crops phosphorus losses require greater amounts of water for dilution than for nitrogen, while pesticides result in the greatest water quality use. Estimates of water quality use are based on assumptions for a number of input variables (i.e. fertilizer application rates, percentage loss of agrochemicals from cropped areas). A Monte Carlo analysis (5000 iterations) was run to randomly select input variables from within defined ranges. Water quality use was calculated and expressed as a factor of blue water use. For all crops the average factor indicated that the volume of water required for dilution of all agrochemicals was greater than that required for irrigation. The results of this study clearly indicate that the impacts of agriculture on water quality need to be considered in virtual water trading scenarios. The incorporation of a method to predict impacts on water quality provides a comparative tool which generates a more holistic frame of reference for decision making with regard to impacts on the water resource and virtual water trading. 相似文献
975.
Trading spaces: Calculating embodied Ecological Footprints in international trade using a Product Land Use Matrix (PLUM) 总被引:4,自引:0,他引:4
Daniel D. Moran Mathis C. Wackernagel Benjamin W. Heumann Steven H. Goldfinger 《Ecological Economics》2009,68(7):1938-1951
Nations import and export biophysical resources. With many ecosystems worldwide under mounting stress, countries may be increasingly interested in knowing the extent and origin of their ecological imports and dependencies. In this paper the Ecological Footprint is used as a tool to measure the biophysical (as opposed to financial) value of international trade flows. This paper attempts to answer the following question: How large of an Ecological Footprint does a given country exert inside the borders of each of its trading partners? Records in the UN COMTRADE bilateral trade database are multiplied by a matrix of per-product Footprint yield coefficients to translate from values in dollars and tonnes to units of hectares. The results show that the largest interregional flows are from Latin to North America, and from North America to Asia-Pacific. Grouping countries by GDP, high and middle income countries appear in Footprint terms to trade predominantly with other high and middle income countries and much less with low income countries. 相似文献
976.
This paper develops a theory of optimal fertility behavior under mortality shocks. In an OLG model, young adults determine
their optimal fertility, labor supply and life-cycle consumption with both exogenous child and adult mortality risks. We show
that a rise in adult mortality exerts an ambiguous effect on both net and total fertility in a general equilibrium framework, while child mortality shocks unambiguously lead to a rise in
total fertility, leaving net fertility unchanged. We complement our theory with an empirical analysis using a sample of 39
Sub-Saharan African (SSA) countries over the 1980–2004 period, examining the overall effects of the child and adult mortality
channels on both total and net fertility. We find child mortality to exert a robust, positive impact on total fertility but
no impact on net fertility, whereas a rise in adult mortality is found to negatively influence both total and net fertility.
Given the particular demographic profile of the HIV/AIDS epidemic (killing essentially young, active adults), we then conclude
in favor of an unambiguous negative effect of the HIV/AIDS epidemic on net fertility in SSA. 相似文献
977.
Japan is in the midst of a demographic transition that is larger and more rapid than other OECD countries. We are interested in understanding the role of lower fertility rates and aging for the evolution of Japan's national saving rate. We use a computable general equilibrium model to analyze the response of the saving rate to changes in demographics and total factor productivity. In our model demographic factors account for 2–3 percentage points of the 9% decline in the saving rate between 1990 and 2000 and persistently depress the saving rate in future years. 相似文献
978.
We develop a model in which costly voting in a large, two‐party election is a sequentially rational choice of strategic, self‐interested players who can reward fellow voters by forming stronger ties in a network formation coordination game. The predictions match a variety of stylized facts, including explaining why an individual's voting behavior may depend on what she knows about her friends' actions. Players have imperfect information about others' voting behavior, and we find that some degree of privacy may be necessary for voting in equilibrium, enabling hypocritical but useful social pressure. Our framework applies to any costly prosocial behavior. 相似文献
979.
Jie Li Xingtang Wang Baomin Dong Eden S. H. Yu 《Review of International Economics》2019,27(4):1108-1125
Would a foreign firm’s consumer‐oriented corporate social responsibility (CSR) activities be rewarded by an importing country’s voluntary tariff reduction? The current paper addresses this question in an import‐competing duopoly model with vertical product differentiation. It is shown that the tariff will decrease if the foreign firm switches from a purely profit‐driven firm to a CSR firm. A consumer‐oriented CSR strategy will always hurt the domestic firm’s profit, whereas the relationship between the foreign firm’s profit and CSR sensitivity (the degree to which a firm cares about consumer welfare) is invertedly U‐shaped. When firms’ decisions to switch to CSR are endogeneized, only the foreign firm will become a CSR firm. 相似文献
980.
Well‐Being,Deprivation, and the Great Recession in the U.S.: A Study in A Multidimensional Framework
Shatakshee Dhongde Prasanta K. Pattanaik Yongsheng Xu 《Review of Income and Wealth》2019,65(Z1):S281-S306
We study changes in social well‐being and deprivation in the U.S. during the Great Recession and the subsequent recovery. We outline an analytical framework for measuring well‐being and deprivation in a multidimensional fashion when data on achievement in each dimension is assumed to be ordinal and binary in nature. We use data from the American Community Survey between 2008 and 2015 and find that there was a decline in social well‐being and a rise in social deprivation in the U.S. during the recession followed by a reversal of trends during the recovery. Despite low deprivation levels among the White population, this population experienced the largest increase in deprivation during the recession and the least decline in deprivation in the recovery period. These results underscore the fact that the impact of recession and the subsequent recovery varied significantly across population groups. 相似文献