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1.
This article presents a flood risk analysis model that considers the spatially heterogeneous nature of flood events. The basic concept of this approach is to generate a large sample of flood events that can be regarded as temporal extrapolation of flood events. These are combined with cumulative flood impact indicators, such as building damages, to finally derive time series of damages for risk estimation. Therefore, a multivariate modeling procedure that is able to take into account the spatial characteristics of flooding, the regionalization method top‐kriging, and three different impact indicators are combined in a model chain. Eventually, the expected annual flood impact (e.g., expected annual damages) and the flood impact associated with a low probability of occurrence are determined for a study area. The risk model has the potential to augment the understanding of flood risk in a region and thereby contribute to enhanced risk management of, for example, risk analysts and policymakers or insurance companies. The modeling framework was successfully applied in a proof‐of‐concept exercise in Vorarlberg (Austria). The results of the case study show that risk analysis has to be based on spatially heterogeneous flood events in order to estimate flood risk adequately.  相似文献   
2.
Abstract.  Recurrent event data are largely characterized by the rate function but smoothing techniques for estimating the rate function have never been rigorously developed or studied in statistical literature. This paper considers the moment and least squares methods for estimating the rate function from recurrent event data. With an independent censoring assumption on the recurrent event process, we study statistical properties of the proposed estimators and propose bootstrap procedures for the bandwidth selection and for the approximation of confidence intervals in the estimation of the occurrence rate function. It is identified that the moment method without resmoothing via a smaller bandwidth will produce a curve with nicks occurring at the censoring times, whereas there is no such problem with the least squares method. Furthermore, the asymptotic variance of the least squares estimator is shown to be smaller under regularity conditions. However, in the implementation of the bootstrap procedures, the moment method is computationally more efficient than the least squares method because the former approach uses condensed bootstrap data. The performance of the proposed procedures is studied through Monte Carlo simulations and an epidemiological example on intravenous drug users.  相似文献   
3.
阐述了或有事项引起的财务报表变动 ,建立了一套财务指标 ,分析了或有事项对企业财务能力的影响 ,并指出在不确定性会计处理中应注意的几个问题  相似文献   
4.
清初,在祖国统一的大业中,各民族的爱国志士都曾为此做出了贡献,蒙古族高僧大德咱雅班智达.南喀嘉措便是在西藏地方归顺清朝中央,实现祖国统一过程中做出过重要贡献的人物之一。鉴于其在历史发展过程中的重要贡献,当时西藏上层以他为首世,建立了“咱雅班智达“转世系统,从此,它成为藏传佛教在蒙古族地区颇具影响的活佛世系之一。  相似文献   
5.
Not having a variance estimator is a seriously weak point of a sampling design from a practical perspective. This paper provides unbiased variance estimators for several sampling designs based on inverse sampling, both with and without an adaptive component. It proposes a new design, which is called the general inverse sampling design, that avoids sampling an infeasibly large number of units. The paper provide estimators for this design as well as its adaptive modification. A simple artificial example is used to demonstrate the computations. The adaptive and non‐adaptive designs are compared using simulations based on real data sets. The results indicate that, for appropriate populations, the adaptive version can have a substantial variance reduction compared with the non‐adaptive version. Also, adaptive general inverse sampling with a limitation on the initial sample size has a greater variance reduction than without the limitation.  相似文献   
6.
社会认知经典研究述评   总被引:1,自引:0,他引:1  
社会认知是指个人对他人或自己的心理与行为的感知与判断的过程。从 1 93 0年代开始 ,社会心理学家就已经对此问题开展研究。 1 947年 ,J.S .Bruner在以往研究基础上 ,提出了社会知觉概念 ,并且进行了相关实验 ,开启了现当代社会认知研究的大门。 1 970年代后 ,社会认知研究开始广泛借鉴认知心理学的理论和方法 ,尤其受到信息加工理论的深刻影响 ,开展了大量的实证研究。文章在把握社会认知研究的历史脉络基础上 ,评述几个在社会认知研究发展史中占有重要地位的经典研究。  相似文献   
7.
The author presents a multivariate location model for cluster correlated observations. He proposes an affine‐invariant multivariate sign statistic for testing the value of the location parameter. His statistic is an adaptation of that proposed by Randles (2000). The author shows, under very mild conditions, that his test statistic is asymptotically distributed as a chi‐squared random variable under the null hypothesis. In particular, the test can be used for skewed populations. In the context of a general multivariate normal model, the author obtains values of his test's Pitman asymptotic efficiency relative to another test based on the overall average. He shows that there is an improvement in the relative performance of the new test as soon as intra‐cluster correlation is present Even in the univariate case, the new test can be very competitive for Gaussian data. Furthermore, the statistic is easy to compute, even for large dimensional data. The author shows through simulations that his test performs well compared to the average‐based test. He illustrates its use with real data.  相似文献   
8.
When a researcher enters an interview, she has already construed it as being a standard type of communicative event. This article considers how a researcher's construal of a communicative event as either an ethnographic or survey interview shapes the production of information. Interview standards entail epistemological assumptions that directly inform the type of information sought and produced. I consider this process through a comparison of the elicitation techniques I employed in survey and ethnographic interviews conducted during research in Mexico. I draw on theory in linguistic anthropology on the nature of meaning in language, examining how dialogicality and interaction are essential to understanding the construal of communicative events.  相似文献   
9.
基于知识治理视角,构建农产品电商集群企业地理邻近性、知识治理、知识共享和协同创新绩效关系的链式中介模型,并引入网络关系强度作为调节变量,结合341家农产品电商集群企业的调研数据,采用多层次回归和Bootstrap分析方法,分析地理邻近性对协同创新绩效的直接作用,检验知识治理和知识共享的独立中介作用和链式中介作用,以及网络关系强度的调节作用。结果表明:地理邻近性正向影响协同创新绩效;知识治理在地理邻近性和协同创新绩效间发挥中介作用;知识共享在知识治理和协同创新绩效间发挥中介作用;知识治理和知识共享在地理邻近性和协同创新绩效间发挥链式中介作用;网络关系强度正向调节正式知识治理和显性知识共享的链式中介作用。因此,农产品电商集群企业要把握数字经济发展契机,善于利用集群区位优势和产业资源,激发正式知识治理和非正式知识治理的双重效应,与合作企业建立良好的知识共享关系,实现高质量协同创新发展。  相似文献   
10.
We study, from the standpoint of coherence, comparative probabilities on an arbitrary familyE of conditional events. Given a binary relation ·, coherence conditions on · are related to de Finetti's coherent betting system: we consider their connections to the usual properties of comparative probability and to the possibility of numerical representations of ·. In this context, the numerical reference frame is that of de Finetti's coherent subjective conditional probability, which is not introduced (as in Kolmogoroff's approach) through a ratio between probability measures.Another relevant feature of our approach is that the family & need not have any particular algebraic structure, so that the ordering can be initially given for a few conditional events of interest and then possibly extended by a step-by-step procedure, preserving coherence.  相似文献   
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