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931.
Accounting for the ecosystem services of migratory species: Quantifying migration support and spatial subsidies 总被引:1,自引:0,他引:1
Migratory species support ecosystem process and function in multiple areas, establishing ecological linkages between their different habitats. As they travel, migratory species also provide ecosystem services to people in many different locations. Previous research suggests there may be spatial mismatches between locations where humans use services and the ecosystems that produce them. This occurs with migratory species, between the areas that most support the species' population viability - and hence their long-term ability to provide services - and the locations where species provide the most ecosystem services. This paper presents a conceptual framework for estimating how much a particular location supports the provision of ecosystem services in other locations, and for estimating the extent to which local benefits are dependent upon other locations. We also describe a method for estimating the net payment, or subsidy, owed by or to a location that balances benefits received and support provided by locations throughout the migratory range of multiple species. The ability to quantify these spatial subsidies could provide a foundation for the establishment of markets that incentivize cross-jurisdictional cooperative management of migratory species. It could also provide a mechanism for resolving conflicts over the sustainable and equitable allocation of exploited migratory species. 相似文献
932.
Santiago M. López Francisco J. Santos-Arteaga 《Structural Change and Economic Dynamics》2011,22(2):106-115
We study an endogenous growth model of technology assimilation through an adaptive learning process defining the accumulation of technological knowledge among both workers and industrial clusters. The assimilation of new technology and the arrival rate of innovations are both based on the distance from the technological frontier to the current technological development level of the country. We illustrate how, even if technological innovations become immediately available to all countries, and absent educational and institutional frictions among countries, differences in technological development levels allow for the existence of poverty traps leading to the economic stagnation of technological laggards. 相似文献
933.
This paper utilizes data on subjective probabilities to study the impact of the stock market crash of 2008 on households' expectations about the returns on the stock market index. We use data from the Health and Retirement Study that was fielded in February 2008 through February 2009. The effect of the crash is identified from the date of the interview, which is shown to be exogenous to previous stock market expectations. We estimate the effect of the crash on the population average of expected returns, the population average of the uncertainty about returns (subjective standard deviation), and the cross-sectional heterogeneity in expected returns (disagreement). We show estimates from simple reduced-form regressions on probability answers as well as from a more structural model that focuses on the parameters of interest and separates survey noise from relevant heterogeneity. We find a temporary increase in the population average of expectations and uncertainty right after the crash. The effect on cross-sectional heterogeneity is more significant and longer lasting, which implies substantial long-term increase in disagreement. The increase in disagreement is larger among the stockholders, the more informed, and those with higher cognitive capacity, and disagreement co-moves with trading volume and volatility in the market. 相似文献
934.
Philip J. Reny 《Economic Theory》2011,48(1):17-29
An infinite game is approximated by restricting the players to finite subsets of their pure strategy spaces. A strategic approximationof an infinite game is a countable subset of pure strategies with the property that limits of all equilibria of all sequences
of approximating games whose finite strategy sets eventually include each member of the countable set must be equilibria of
the infinite game. We provide conditions under which infinite games admit strategic approximations. 相似文献
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938.
Philip J. VergragtAuthor Vitae Jaco QuistAuthor Vitae 《Technological Forecasting and Social Change》2011,78(5):747-755
In this introductory paper we introduce the special issue on “Backcasting for Sustainability”. We present briefly a historical background, and position backcasting in the wider context of future studies, in which it can be related to “normative forecasting” and normative scenarios. We reflect on the diversity and variety of backcasting studies and experiments, as presented in the ten papers for this special issue. After summarizing the papers we formulate a future research agenda. 相似文献
939.
John J. Horton 《Economics Letters》2011,111(1):10-12
Critics of online labor markets claim that employer abuses are endemic in these markets. Surveying a sample of workers, I find that, on average, workers perceive online employers to be slightly fairer and more honest than offline employers. 相似文献
940.
We show that attractiveness, as measured by facial symmetry, leads to greater rewards in professional sports. National Football League quarterbacks who are more attractive are paid greater salaries and this premium persists after controlling for player performance. 相似文献