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11.
Christophe Didier 《Risk analysis》2009,29(10):1347-1354
Even if most French mines are definitively closed, potential risks remain above the abandoned sites. In addition to surface instability, some mining sites may be affected by dangerous gas emissions, flooding events, or environmental impacts. Those kinds of disorders strongly influence the land-use management of the concerned areas. The present article presents the French mining historical context and identifies the major kinds of residual risks and harmful effects that may affect abandoned mine sites. The prevention policy applied on the national territory is then discussed and prospects for further developments are proposed.  相似文献   
12.
It has been reported that familiarity or incidental similarities with a stranger influenced an individual’s behavior. However, the effect of the sense of geographical proximity believing that someone comes from the same area that somebody has never been examined. Three field experiments examined this effect on donations to humanitarian organizations. In the first study, participants were asked by a confederate to donate food products to a humanitarian organization. In Study 2, participants were asked by confederates to donate money for children. In Study 3, donation boxes were displayed in bakeries with a message that invited customers to donate money for children. In all the studies, participants were led to believe that they would be helping people in need or people who live in their national or local geographic area. Results showed that donations were higher in the geographical proximity condition. This “neighborhood effect” was discussed.  相似文献   
13.
ABSTRACT

We study the estimation of a hazard rate function based on censored data by non-linear wavelet method. We provide an asymptotic formula for the mean integrated squared error (MISE) of nonlinear wavelet-based hazard rate estimators under randomly censored data. We show this MISE formula, when the underlying hazard rate function and censoring distribution function are only piecewise smooth, has the same expansion as analogous kernel estimators, a feature not available for the kernel estimators. In addition, we establish an asymptotic normality of the nonlinear wavelet estimator.  相似文献   
14.
Many economic duration variables are often available only up to intervals, and not up to exact points. However, continuous time duration models are conceptually superior to discrete ones. Hence, in duration analyses, one faces a situation with discrete data and a continuous model. This paper discusses (i) the asymptotic bias of a conventional approximation procedure in which a discrete duration is treated as an exact observation; and (ii) the efficiency of a correct maximum likelihood estimator which appropriately accounts for the discrete nature of the data.  相似文献   
15.
中国的翻译界将艺术创作领域内的"形似"、"神似"借来,作为处理译文的两种方法,并曾产生了不小的争论.追溯历史,有比较固定内涵的"形"、"神"概念,大约盛行于春秋战国,深入于两汉,而分化于晋以后.争执起因是很多学人心目中的"形"与"神"是截然分开的两个单一概念.实际上,"形"与"神"是密切相关的两个多层次概念.最理想的情况无疑是形神兼备.在不能两全时,译者必然面临抉择.在这种情况下,译者试图表达作者意图和保证原作声誉的任何努力都应得到应有的肯定.  相似文献   
16.
Rongfang Yan  Gaofeng Da 《Statistics》2013,47(5):1128-1140
In this paper, we investigate ordering properties of lifetimes of parallel systems with two independent heterogeneous exponential components with respect to likelihood ratio and hazard rate orders. Two sufficient conditions are provided for likelihood ratio and hazard rate orders to hold between the lifetimes of two parallel systems, respectively. Moreover, we extend the results from exponential case to the proportional hazard rate models. The results established here strength some of the results known in the literature. Finally, some numerical examples are given to illustrate the theoretical results derived here as well.  相似文献   
17.
The study is based on a sample of 965 children living in Oulu region (Finland), who were monitored for acute middle ear infections from birth to the age of two years. We introduce a nonparametrically defined intensity model for ear infections, which involves both fixed and time dependent covariates, such as calendar time, current age, length of breast-feeding time until present, or current type of day care. Unmeasured heterogeneity, which manifests itself in frequent infections in some children and rare in others and which cannot be explained in terms of the known covariates, is modelled by using individual frailty parameters. A Bayesian approach is proposed to solve the inferential problem. The numerical work is carried out by Monte Carlo integration (Metropolis-Hastings algorithm).  相似文献   
18.
The number of sterile couples in a retrospective study of the number of cycles to conception is necessarily zero; this is not so for a prospective study. The paper puts forward a modification of Weinberg and Gladen's beta geometric model for cycles to conception that is suitable for both types of investigation. The probability that a couple achieves conception at the xth cycle, but not earlier, is assumed to take the form Rx = (1 ? ρ)/(1 ? m x?1 ρ/u), instead of μ/(1 ? θ + θx). The set of parameter restraints (0 < m < 1, 0< ρ < 1, 1 < u) is appropriate for retrospective data, whilst the alternative set of restraints (1 < m, 1 < ρ, 0 < u < 1) is appropriate for prospective data. The decrease in Rx over time can be interpreted not only as a time effect, but also as a heterogeneity effect by replacing Weinberg and Gladen's beta mixture of geometric distributions by a q-beta mixture.  相似文献   
19.
Two different distributions may have equal Rényi entropy; thus a distribution cannot be identified by its Rényi entropy. In this paper, we explore properties of the Rényi entropy of order statistics. Several characterizations are established based on the Rényi entropy of order statistics and record values. These include characterizations of a distribution on the basis of the differences between Rényi entropies of sequences of order statistics and the parent distribution.  相似文献   
20.
科学联想是在科学研究过程中,人们根据事物之间的某种联系,由一种事物想到另一种相关事物的思维活动。按照科学联想的性质和特点的不同,科学联想可分为接近联想、对比联想、类比联想和因果联想四种类型。科学联想是一种重要的科技创新思维,加强联想能力的训练是提高联想能力的有效途径。  相似文献   
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