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191.
    
Successful land claims on protected areas by previously disenfranchised communities often result in co-management agreements between claimant communities and state conservation agencies. South Africa, in particular, has pursued co-management as the desired outcome of land claims on its protected areas. We review four cases of co-management on protected areas in South Africa, and reflect on the appropriateness of the pursuit of co-management as the preferred outcome of land claims. Despite promises of pro-poor, democratically informed management, the practical experience of co-management has seen the continuation of the status quo in terms of conservation, with very few material benefits for claimant communities and limited sharing of responsibilities and decision-making functions. The findings underscore two deep challenges facing co-management in cases of land claims worldwide. First, during land claims negotiations in cases involving protected areas, the state cannot be expected to represent the best interests of its citizens (the land claimants), while simultaneously seeking to meet national and international obligations for protected area coverage. Second, the concept of democratic co-management may sit uncomfortably beside the realities of managing loss-making protected areas with ever-shrinking conservation budgets. Where co-management agreements have already been signed, ensuring that new landowners do indeed have a say in management should form the driving focus for co-management practice going forward.  相似文献   
192.
    
The United States Agency for International Development (USAID), like many other development agencies and donors, increasingly emphasizes evidence-based programming. This requires assessments of project performance at all stages of implementation, comprising ex-ante impact assessment, monitoring and evaluation, and ex-post attribution of outcomes. Ex-ante impact assessment, in particular, involves performing Cost-Benefit Analysis (CBA) to determine the Expected Net Present Value (ENPV) of the project in question. Unfortunately, the traditional ENPV approach has proven inadequate for dealing with uncertainty in the timing of investments and flexibility in future decision making. This is especially relevant for Research and Development (R&D) projects which require several stages of product development and multiple rounds of testing prior to releasing final products. As a consequence, the real-options approach to CBA has increasingly been used to evaluate private sector R&D projects. This paper advocates for the adoption of the real options approach in the evaluation of public investments in agricultural research, and illustrates its practical utility with an assessment conducted by USAID to determine the economic viability of a proposed project to develop improved varieties of critical food security crops in Uganda.  相似文献   
193.
    
A game contingent claim is a contract which enables both the buyer and the seller to terminate it before maturity. For complete markets Kifer [Finance and Stochastics 4 (2000) 443–463] shows a connection to a (zero-sum) Dynkin game whose value is the unique no-arbitrage price of the claim. But, for incomplete markets one needs a more general approach. We interpret the contract as a generalized non-zero-sum stopping game. For the complete case this leads to the same results as in Kifer [Finance and Stochastics 4 (2000) 443–463]. For the general case we show the existence of an equilibrium point under the condition that both the seller and the buyer have an exponential utility function. For other utility functions such a point need not exist in the context of incomplete markets.  相似文献   
194.
    
This paper presents an analysis of the concept of scientific substantiation in European health claims regulation. It focuses on the controversies about the demand for the establishment of cause-and-effect relationships between food consumption and health outcomes in claim substantiation. Our analysis, on the basis of regulatory and scientific documents, identifies two opposing views about the aims of health claims regulation. Each of these two stances links certain regulatory objectives with specific epistemic policies, that is particular sets of scientific methodology, criteria, and procedure. The regulators, in selecting a demanding evidentiary approach based on a hierarchy of methodologies that requires causal data for substantiation of claims, give priority to preventing the authorization of false claims. The opposing view, espoused by the critics of this approach, opts for less demanding requirements for substantiation, implying the market availability of a wider range of products with health claims that may provide individual as well as public health benefits. We argue that one of the objectives that underlie the European regulators’ demand for causal data is to protect their own credibility, by trying to isolate them from value-laden debates about the limitations of scientific methodologies, as well as the societal and policy implications of regulatory decision-making.  相似文献   
195.
    
Abstract

Although consumers' growing interest in ethical consumption has been well-documented, their understanding of specific claims, and the link between their stated concerns and behaviour, has not. Using a framework from systematic-heuristic and behaviour modification theory, this study explored consumers' understanding of varied ethical claims and a specific eco-label, and then estimated the effect these stimuli had on their choice behaviours. In-depth interviews revealed a strong interest in environmental and social attributes but considerable scepticism about specific claims. However, a choice modelling experiment found ethical attributes nevertheless influenced respondents' choices. Two distinct clusters whose views and choice behaviours differed markedly existed: one was primarily price-driven and the other more responsive to specific claims. Discrepancies between the qualitative and quantitative studies appear attributable to differences in information processing; many consumers respond strongly to heuristics, even though they believe themselves sceptical of the claims these communicate. The findings raise important policy questions about the scientific basis of many ethical claims, since consumers were strongly influenced by these, despite their views to the contrary.  相似文献   
196.
This study tests the effect of health-related ad information on perceived product healthfulness and purchase intention. Also, the study investigates whether consumers' health motivation moderates the effects, because of the way health motivation affects processing of health-related information in ads. Three types of health-related ad elements are distinguished: functional claims, process claims and health imagery. These elements were combined in mock ads and an online experiment was run to test the study hypotheses. Results show that health imagery has the largest impact on consumers' product evaluations, while functional claims and process claims have much smaller effects. Health motivation shows significant interaction with process claims on product evaluations.  相似文献   
197.
This article frames GSS-enabled interventions as electronically supported discourses, designed and evaluated against a gold standard of ideal speech in a perfect communication environment. The objectives are, firstly, to develop a model of GSS-enabled interventions based on Habermas' theory of communicative action, and secondly, to apply the model as a problem-structuring device to the conceptual problem of designing the strategic evaluation of a comprehensive urban plan. The model, known as the VC (validity claims) Model, provides separate evaluative criteria for personal, social and technical aspects. The criteria for successful GSS-enabled interventions may be summarized as personal commitment (validated by personal truthfulness or sincerity), to a social consensus (validated by rightness), for informed action (validated by objective truth). Detailed criteria (viz., goal, strategy, procedure, issues, problems) are developed for each type of validity claim and matched to the technologies available. The result is a detailed brief illustrating the design of a GSS-enabled strategic urban planning intervention, including a sample agenda for the GSS-supported meeting and the GSS tools that will be employed.  相似文献   
198.
The relative merits of different systems of property rights to allocate water among different extractive uses are evaluated for the case where variability of supply is important. Three systems of property rights are considered. In the first, variable supply is dealt with through the use of water entitlements defined as shares of the total quantity available. In the second, there are two types of water entitlements, one for water with a high security of supply and the other a lower security right for the residual supply. The third is a system of entitlements specified as state‐contingent claims. With zero transaction costs, all systems are efficient. In the realistic situation where transaction costs matter, the system based on state‐contingent claims is globally optimal, and the system with high‐security and lower security entitlements is preferable to the system with share entitlements.  相似文献   
199.
This paper addressed consumers’ attitude towards food labels and the influence of different aspects of meat labels on beef, poultry and seafood consumption using data from a national survey in the USA. Approximately 70% of the respondents reported that food labels helped in the purchases of beef and other meat products. While 50% thought that the present level of information on meat labels was about right, about 30% thought that it was insufficient. Similarly, 80, 81, 60, and 80% of the respondents thought that it was very important that meat labels contain information regarding nutrition, ingredients, health claim, and production process respectively. Those respondents who thought that nutrition and ingredient information on food labels were very important also thought that meat labels helped them select beef and other meat products. Consumer preferences for nutrition and ingredient information on food labels were positively related with meat consumption frequency.  相似文献   
200.
Healthtrac Rewards is a US‐based, workplace wellness intervention promoting healthy behaviour through voluntary self‐reporting of participants' dietary habits, physical activity and medical concerns. Monthly financial incentives encourage either primary participation or secondary participation requiring additional interaction with Healthtrac personnel. Using data from 17 533 eligible employees, the purpose of the study was to determine whether Healthtrac participants consumed fewer healthcare services, as measured by 2004 medical claim costs or numbers of procedures, relative to non‐participants. High‐cost individuals tended to self‐select into the programme. Costs were 22–27% greater among participants after controlling for other factors. Participants consumed more preventive care, however, which was correlated with reduced future procedures. The secondary intervention was more effective than the primary intervention, suggesting a priority on increasing intensity of involvement vs. basic enrolment.  相似文献   
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