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51.
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As the hunting, butchering, processing, and consumption of bushmeat is a potential source of human Ebola virus (EV) infections, the extent to which bushmeat is a substitute for food produced and sold in the formal sector suggests that the relative price of food could matter for the incidence of human EV infections. This paper considers if productivity in the food sector is a driver of human EV infections in sub‐Saharan Africa. We estimate count data specifications of country level human EV infections as a function of food sector productivity in sub‐Saharan Africa over the 1976–2013 time period. Our parameter estimates suggest that if productivity in the food sector was on average 1 per cent higher over the 1976–2013 time period, the incidence of human EV infection would have been 42.5 per cent lower. This is consistent with bushmeat being a substitute for food produced in the formal sector, as food productivity increases lower the price of formal food relative to bushmeat. Our findings suggest that as productivity in the formal food sector is a driver of human EV infections in sub‐Saharan Africa, policy interventions that increase food productivity would enable Millennium Development Goal outcomes related to hunger, disease mitigation, and sustainability of wildlife.  相似文献   
53.
The Carpathian Basin is one of the most vulnerable European regions in terms of potential climate change impacts on biodiversity. Its wide range of tourism activities make it uniquely suitable for assessing the effects of climate change on tourism. This research sought to create a Tourism Adaptation Portfolio (TAP) for the Szentendre micro-region in Hungary and to assemble an adaptation toolbox for current and future use by tourism organizations. The TAP contains practical, easy to implement solutions for key stakeholders in the sector by adaptation type (technology, management, behavior, education, policy). Surveys of local tourism suppliers showed that 70% said they were well informed, largely by the Internet, but 55% admitted to not knowing enough. The methodology outlined here is transferable and the process can be replicated elsewhere, supporting other regions in becoming climate-friendly tourism destinations, creating opportunities for uniquely positioning a region for consumers. The article provides a concise overview of tourism provider attitudes assessed through a questionnaire, shedding light on points of intervention, willingness to pay, main barriers and suitable adaptation instruments. The adaptive capacity of stakeholders is also discussed, which is indispensable for implementing successful practices in adaptation and maintaining the current level of environmental services.  相似文献   
54.
Risk,uncertainty and the theory of planned behavior: A tourism example   总被引:1,自引:0,他引:1  
The differential impacts risk and uncertainty have on travel decision-making were explored by examining the constructs' influence on the antecedents of intentions to visit Australia using the theory of planned behavior. Respondents were obtained from online consumer panels in South Korea, China and Japan. The South Korean and Chinese samples were general population samples, while the sample from Japan was an international travelers' sample. The extended model fitted the data well, explaining between 21 and 44 percent of the variance in intentions. Subjective norms and perceived behavioral control significantly impacted on intentions in all country samples, whereas attitudes toward visiting Australia were only significant in Japan. Subjective norms influenced attitudes and perceived behavioral control in all country samples. Finally, perceived risk influenced attitudes toward visiting Australia in South Korea and Japan, while perceived uncertainty influenced attitudes toward visiting Australia in South Korea and China and perceived behavioral control in China and Japan.  相似文献   
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We study how the sequence of financing of R&D varies according to the ease with which property rights over knowledge can be defined. There are two financiers: a venture capitalist (VC) and a corporation. The knowledge acquired in costly research becomes embodied in the researcher's human capital, and she may hold up the financier and walk away with the project to develop it elsewhere. The main results are: (1) When property rights are strong, research is always funded by the VC, development is performed efficiently, and breakaways from the VC to the corporation are observed in equilibrium. (2) When property rights are weak, projects may be financed by the VC or the corporation, or may remain unfunded. (3) When property rights are weak, no breakaways occur in equilibrium; local spillovers and strong product market competition increase the likelihood that research projects will get funding. (4) The equilibrium sequence of R&D finance need not be first-best efficient. (5) In equilibrium, and controlling for the strength of property rights, VCs finance projects that are more profitable on average.  相似文献   
57.
For reasons of time constraint and cost reduction, censoring is commonly employed in practice, especially in reliability engineering. Among various censoring schemes, progressive Type-I right censoring provides not only the practical advantage of known termination time but also greater flexibility to the experimenter in the design stage by allowing for the removal of test units at non-terminal time points. In this article, we consider a progressively Type-I censored life-test under the assumption that the lifetime of each test unit is exponentially distributed. For small to moderate sample sizes, a practical modification is proposed to the censoring scheme in order to guarantee a feasible life-test under progressive Type-I censoring. Under this setup, we obtain the maximum likelihood estimator (MLE) of the unknown mean parameter and derive the exact sampling distribution of the MLE under the condition that its existence is ensured. Using the exact distribution of the MLE as well as its asymptotic distribution and the parametric bootstrap method, we then discuss the construction of confidence intervals for the mean parameter and their performance is assessed through Monte Carlo simulations. Finally, an example is presented in order to illustrate all the methods of inference discussed here.  相似文献   
58.
Let X 1, . . . , X n be independent exponential random variables with respective hazard rates λ1, . . . , λ n , and Y 1, . . . , Y n be independent and identically distributed random variables from an exponential distribution with hazard rate λ. Then, we prove that X 2:n , the second order statistic from X 1, . . . , X n , is larger than Y 2:n , the second order statistic from Y 1, . . . , Y n , in terms of the dispersive order if and only if
$\lambda\geq \sqrt{\frac{1}{{n\choose 2}}\sum_{1\leq i < j\leq n}\lambda_i\lambda_j}.$
We also show that X 2:n is smaller than Y 2:n in terms of the dispersive order if and only if
$ \lambda\le\frac{\sum^{n}_{i=1} \lambda_i-{\rm max}_{1\leq i\leq n} \lambda_i}{n-1}. $
Moreover, we extend the above two results to the proportional hazard rates model. These two results established here form nice extensions of the corresponding results on hazard rate, likelihood ratio, and MRL orderings established recently by Pǎltǎnea (J Stat Plan Inference 138:1993–1997, 2008), Zhao et al. (J Multivar Anal 100:952–962, 2009), and Zhao and Balakrishnan (J Stat Plan Inference 139:3027–3037, 2009), respectively.
  相似文献   
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Los autores comparan las normativas sobre vacaciones y licencias susceptibles de facilitar el equilibrio entre vida profesional y familiar de Australia, Canadá, República de Corea, Estados Unidos, Europa occidental y Japón utilizando un índice compuesto para clasificarlas. Los Estados Unidos figuran en último lugar: la concesión de vacaciones anuales al trabajador no es obligatoria y las licencias por motivos familiares se limitan a 12 semanas al año. Este bajo nivel de reglamentación podría deberse, según los autores, a una concepción mercantilista del empleo sumada a la creencia de que empleador y trabajadores tienen idéntica capacidad de negociación, visión no compartida por las demás democracias industrializadas.  相似文献   
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