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As a form of environmental governance, Payments for Ecosystem Services (PES) is imbued with ideological values that can conflict with those of participating rural communities. The discursive frame surrounding PES may be contentious, even if the conservation activities promoted by these initiatives are not. Moving PES into practice therefore requires a process of translation from urban-based practitioners to rural communities. Drawing upon an empirical case study of FONAG, a water fund from Ecuador that is often promoted as the ideal type, this article employs data from participant observation, key informant interviews and textual materials to examine this process of translation. The article focuses particularly on the efforts to negotiate the discourse of PES that move the projects into on-the-ground practice. While Ecuador's political context has softened the emphasis on economically valuing ecosystem services, FONAG uses neoliberal conservation narratives that identify rural poverty as the main cause of environmental degradation and target the reform of local people through economic incentives. To enrol communities, however, intermediaries are needed to translate water fund PES to appeal to local perspectives, values and institutions. The author argues that contrasting narratives of PES can exist simultaneously between the entities that are implementing PES and the targets of that implementation.  相似文献   
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Optimal Sampling Design for Variables with Varying Spatial Importance   总被引:1,自引:0,他引:1  
It is often desirable to sample in those locations where uncertainty associated with a variable is highest. However, the importance of knowing the variable's value may vary across space. We are interested in the spatial distribution of Received Signal Strength Indicator (RSSI), a measure of the signal strength from a cell tower received at a particular location. It is crucial to estimate RSSI values accurately in order to evaluate the effectiveness of mayday systems designed for rapid emergency notification following vehicle crashes. RSSI estimation is less important for locations where the probability of a crash is low and where the likelihood of call completion is either close to zero or one. We develop a method for augmenting an initial spatial sample of RSSI values to achieve a high‐precision estimate of the probability of call completion following a crash. We illustrate the approach using data on RSSI and vehicle crashes in Erie County, NY.  相似文献   
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This paper provides a comprehensive analysis of the pattern of hospital utilization (rather than provision) in England prior to the establishment of the NHS, showing the extent to which the probability of obtaining hospital treatment was a function of residence. Access to hospital care depended on the vigour of voluntarism and the political priorities of local governments. The pattern of voluntary hospital utilization is shown to have been markedly unequal, but the effect of municipal provision was to reduce disparities in access to services. The paper demonstrates variations in hospital utilization and discusses contemporary assessments of the situation. This work contributes to debates about the efficacy of non-profit forms of welfare delivery; it provides a novel British study to complement American work in this field. It also raises questions about the contemporary vogue for partnerships in health care delivery between the public and private sectors, arguing that such proposals rest on an optimistic view of history.  相似文献   
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In this article, we address the problem of allocating an additional cell tower (or a set of towers) to an existing cellular network, maximizing the call completion probability. Our approach is derived from the adaptive spatial sampling problem using kriging, capitalizing on spatial correlation between cell phone signal strength data points and accounting for terrain morphology. Cell phone demand is reflected by population counts in the form of weights. The objective function, which is the weighted call completion probability, is highly nonlinear and complex (nondifferentiable and discontinuous). Sequential and simultaneous discrete optimization techniques are presented, and heuristics such as simulated annealing and Nelder–Mead are suggested to solve our problem. The adaptive spatial sampling problem is defined and related to the additional facility location problem. The approach is illustrated using data on cell phone call completion probability in a rural region of Erie County in western New York, and accounts for terrain variation using a line‐of‐sight approach. Finally, the computational results of sequential and simultaneous approaches are compared. Our model is also applicable to other facility location problems that aim to minimize the uncertainty associated with a customer visiting a new facility that has been added to an existing set of facilities.  相似文献   
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