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61.
When sampling from a continuous population (or distribution), we often want a rather small sample due to some cost attached to processing the sample or to collecting information in the field. Moreover, a probability sample that allows for design‐based statistical inference is often desired. Given these requirements, we want to reduce the sampling variance of the Horvitz–Thompson estimator as much as possible. To achieve this, we introduce different approaches to using the local pivotal method for selecting well‐spread samples from multidimensional continuous populations. The results of a simulation study clearly indicate that we succeed in selecting spatially balanced samples and improve the efficiency of the Horvitz–Thompson estimator.  相似文献   
62.
We urgently need to put the concept of resilience into practice if we are to prepare our communities for climate change and exacerbated natural hazards. Yet, despite the extensive discussion surrounding community resilience, operationalizing the concept remains challenging. The dominant approaches for assessing resilience focus on either evaluating community characteristics or infrastructure functionality. While both remain useful, they have several limitations to their ability to provide actionable insight. More importantly, the current conceptualizations do not consider essential services or how access is impaired by hazards. We argue that people need access to services such as food, education, health care, and cultural amenities, in addition to water, power, sanitation, and communications, to get back some semblance of normal life. Providing equitable access to these types of services and quickly restoring that access following a disruption are paramount to community resilience. We propose a new conceptualization of community resilience that is based on access to essential services. This reframing of resilience facilitates a new measure of resilience that is spatially explicit and operational. Using two illustrative examples from the impacts of Hurricanes Florence and Michael, we demonstrate how decisionmakers and planners can use this framework to visualize the effect of a hazard and quantify resilience-enhancing interventions. This “equitable access to essentials” approach to community resilience integrates with spatial planning, and will enable communities not only to “bounce back” from a disruption, but to “bound forward” and improve the resilience and quality of life for all residents.  相似文献   
63.
This article presents methodological solutions aimed at presenting the spatial distribution of flood risk and quality of spatial management (land use), indicating both those areas used reasonably and those requiring modification. The purpose was to identify key risk areas and risk‐free areas from the point of view of human security and activity on the floodplains, based on the examples of the vicinities of Wroclaw and Raciborz in the Odra Valley, Poland. Due to recent climate change, Poland has suffered the effects of severe flooding (e.g., 1997, 2001, 2010). The analyses conducted were motivated by the European Parliament and Council's recently implemented Directive 2007/60/WE, as well as by the demand for studies for local spatial planning. The analysis indicates that reasonably developed areas do not account for the majority of those studied, making up 36% of the Wroclaw area and 15% of the Raciborz area.  相似文献   
64.
有关黄河河源的概念,古代各种史学、地理、以及宗教文献都有相关记载。早期文献中提出的重源潜流的概念,也为塑造河源空间概念留下了发挥余地。及至唐朝,各种类书、笔记、野史关于位于境外的河源的著述沿用了上述文献中已有的地理知识,并融入了佛教世界观的空间概念以及唐代实地考察的纪录,逐渐构成了河源这一多元化的空间想象。本文探讨了不同知识框架对唐代河源记载的影响,以及在几幅现存宋代地图上所反映出的相关影响。这类文献资料有助于我们理解中古地理知识的深化与演变,以及后代地图上展示河源的更丰富的地图表现形式。  相似文献   
65.
Despite strong political commitment, actual gains in improving accountability in development co‐operation have been limited. Main reasons for this include the low level of transparency and high number of actors, as well as the limitations of the self‐reported and input‐oriented OECD reporting system. Efforts through the International Aid Transparency Initiative (IATI) and related transparency initiatives are ill‐equipped to change this given their decision to adhere to the same system. This article uses the specific area of support to capacity development to illustrate this. While further disaggregation of reporting on technical co‐operation could respond to a transparency gap, overcoming the accountability gap requires moving beyond promoting ‘supply‐side’ reform and re‐engaging in efforts to promote collective action.  相似文献   
66.
One-sided confidence regions for continuous cumulative distribution function are constructed using empirical cumulative distribution functions and the generalized Kolmogorov-Smirnov distance. The band width of such regions becomes narrower in the right or left tail of the distribution. Significance levels necessary for implementation are given. Some other K-S type distances useful in constructing a confidence region with nonconstant width are also included.  相似文献   
67.
Clinical phase II trials in oncology are conducted to determine whether the activity of a new anticancer treatment is promising enough to merit further investigation. Two‐stage designs are commonly used for this situation to allow for early termination. Designs proposed in the literature so far have the common drawback that the sample sizes for the two stages have to be specified in the protocol and have to be adhered to strictly during the course of the trial. As a consequence, designs that allow a higher extent of flexibility are desirable. In this article, we propose a new adaptive method that allows an arbitrary modification of the sample size of the second stage using the results of the interim analysis or external information while controlling the type I error rate. If the sample size is not changed during the trial, the proposed design shows very similar characteristics to the optimal two‐stage design proposed by Chang et al. (Biometrics 1987; 43:865–874). However, the new design allows the use of mid‐course information for the planning of the second stage, thus meeting practical requirements when performing clinical phase II trials in oncology. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
68.
从空间批评视角看,文本中的空间不再是静止的"容器",而是一种蕴含多维文化信息的指涉系统,注重文本中空间的社会、文化属性。在美国华裔作家雷祖威的短篇小说《生日》中,与华裔青年华莱士·王的爱情故事相关的几个空间场景不仅再现了华裔的现实生活世界,更充分展示了他们居于社会边缘的处境与内心疏离的痛苦。  相似文献   
69.
The popular generalized extreme value (GEV) distribution has not been a flexible model for extreme values in many areas. We propose a generalization – referred to as the Kumaraswamy GEV distribution – and provide a comprehensive treatment of its mathematical properties. We estimate its parameters by the method of maximum likelihood and provide the observed information matrix. An application to some real data illustrates flexibility of the new model. Finally, some bivariate generalizations of the model are proposed.  相似文献   
70.
Nuria Torrado 《Statistics》2017,51(6):1359-1376
Stochastic ordering relations between extreme order statistics from exponential, Weibull and gamma distributions have been studied extensively by many researchers in recent years. In this work, we obtain various ordering results for the comparisons of two extreme order statistics from scale models when one set of scale parameters majorizes the other. The new results obtained here are applied when the baseline distributions are exponentiated Weibull or generalized gamma distributions. In this way, we generalize and extend some results established recently in the literature.  相似文献   
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