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871.
Ten years ago, the model of creative destruction was developed to predict the fate of communities that base their development on the commodification of rural heritage (Mitchell, C.J.A., 1998. Entrepreneurialism, commodification and creative destruction: a model of post-modern community development. Journal of Rural Studies 14, 273–286). Its application to the village of St. Jacobs, Canada, demonstrated that entrepreneurial investment had fostered the creation of a setting for aestheticized consumption. In this paper we demonstrate that creative destruction has continued to unfold in the village over the course of the past decade. The evolutionary path taken is assessed in light of current literature on rural space. It is concluded that to fully understand the transformative process, one must integrate the demands of myriad sub-cultures, whose social relations, ideologies and actions will contribute to the development of a contested landscape of consumption. This finding necessitates that modifications be made to the model and its various stages. The most significant is recognition that the “heritage-scape” is an interim state of landscape change; one that displaces the productivist landscape of the industrial period, and precedes the creation of the “neo-productivist” leisure-scape of post-industrialism. Whether or not such a “final” state is achieved is dictated by the power struggle that inevitably arises amongst sub-cultures engaged in the transformation of rural space.  相似文献   
872.
Abstract

In this article, we have considered the problem of estimation of population variance on current (second) occasion in two occasion successive (rotation) sampling. A class of estimators of population variance has been proposed and its asymptotic properties have been discussed. The proposed class of estimators is compared with the sample variance estimator when there is no matching from the previous occasion and the Singh et al. (2013) estimator. Optimum replacement policy is discussed. It has been shown that the suggested estimator is more efficient than the Singh et al. (2013) estimator and a usual unbiased estimator when there is no matching. An empirical study is carried out in support of the present study.  相似文献   
873.
A simple approximation for the doubly noncentral t-distribution, based upon the Fieller-Geary Theorem (1930) and approximate normality of the square root of the noncentral chi-square variable observed by Patnaik (1949), is developed, This approximation and an Edgeworth series expansion associated with it are evaluated. The simple approximation is seen to be reasonably accurate for most practical purposes.  相似文献   
874.
Stochastic scenario trees are a new and popular method by which surveillance systems can be analyzed to demonstrate freedom from pests and disease. For multiple component systems—such as a combination of a serological survey and systematically collected observations—it can be difficult to represent the complete system in a tree because many branches are required to represent complex conditional relationships. Here we show that many of the branches of some scenario trees have identical outcomes and are therefore redundant. We demonstrate how to prune branches and derive compact representations of scenario trees using matrix algebra and Bayesian belief networks. The Bayesian network representation is particularly useful for calculation and exposition. It therefore provides a firm basis for arguing disease freedom in international forums.  相似文献   
875.
景观设计是一个基于科学的解决规划和设计问题的艺术性行业。本文根据Jon Bryan Burley博士2007年秋在南京林业大学为规划与设计专业师生所作的第七次演讲的内容,阐述了科学与艺术之间的平衡。Burley博士通过展示和列举他在中国工作时个人手绘作品及在密歇根所做的计算机辅助视觉质量评估工作的案例,描述了艺术和科学之间的区别、标准化的理论和科学理论之间的区别。Burley博士认为,作为设计师,艺术和科学两种方法缺一不可。随着科技的发展变化,新方法和新技术终将完美结合并被专业所接受。  相似文献   
876.
The relative performances of randomised block, balanced lattice squares and Papadakis nearest neighbour analyses were compared on two simulated fields whose soil heterogeneity profiles were generated, one with a few evenly spaced contours and the other with many unevenly spaced contours. Four levels of random error were generated to simulate different proportions of random error and soil heterogeneity. Dummy treatments, corresponding to 7 x 7 and 11 x 11 balanced lattice squares were applied to the fields. The results from simulated experiments showed an interaction of error mean square (EMS) between size of experiment (7 x 7, 11 x 11) and levels of soil heterogeneity in the lattice analyses, but no such interaction in the Papadakis analyses. The Papadakis EMS decreased as random error decreased but at a rate depending on the map andthe ratio of soil heterogeneity to random error.  相似文献   
877.
In performance evaluations, data without explicit inputs (such as index data, pure output data) are widely used. To directly use such data, this paper presents a study on building DEA models without explicit inputs, so-called DEA-WEI models, which are applicable to the evaluation applications where inputs are not directly considered. We provide an axiom foundation of these kinds of models, and further discuss how to incorporate value judgments of decision makers into these DEA-WEI models. Several such models are derived. Finally, applications of the DEA-WEI models are presented.  相似文献   
878.
ABSTRACT

This paper addresses the problem of estimation of the population mean on the current (second) occasion in two-occasion successive sampling. Utilizing the readily available information on several auxiliary variables on both occasions and the information on the study variable from the previous occasion, an estimation procedure of the population mean on the current occasion has been proposed. Theoretical properties of the proposed estimator have been investigated. Optimum replacement policy to the proposed estimator has been discussed. The proposed estimator has been compared empirically with the sample mean estimator, when there is no matching and the optimum estimator which is a linear combination of the means of the matched and unmatched portions of the sample at the current occasion. Appropriate recommendations have been made for practical applications.  相似文献   
879.
The author describes a position of a supervisor in a clinical institution, which he would have rejected some years ago??to adopt a management role as supervisor and to act mainly in the role of a supervisor. But the recent experiences have shown, that this may be possible and successful. This is illustrated by a case study.  相似文献   
880.
Temporary “guestworker” programs are often assumed to have less impact on native-born workers than permanent immigration. However, there are theoretical reasons to expect temporary immigrants to accept lower wages and thus for temporary migration to have a greater adverse impact on receiving country wages. This article develops these theoretical insights and tests for differences in wages paid to temporary and permanent undocumented Mexican immigrants. Survey data from Mexico shows that temporary immigrants earned wages about 12% lower than permanent immigrants. Controlling for human and social capital, a 7.4% difference in wages remains. Among married immigrants, temporary immigrants earn 9.6% lower wages with these same controls.  相似文献   
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