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11.
风险社会的来临改变了人类的生存境遇和生活体验,也必将导致人们观念和行为方式的改变。对现代风险社会进行认真的反思,并将与“人为的不确定性”相联系的风险概念引入,可以消解历史决定论的思维定势,也可以为马克思历史唯物主义的真实意蕴及当代性的彰显提供全新的解释维度和现实根据。  相似文献   
12.
房地产证券化是我国房地产业与金融业发展的一种有机结合 ,它对优化配置与有效利用房地产和资金具有十分重要的意义。它是我国房地产业和金融业发展的客观要求 ,有利于社会资源的分配、稳定证券市场 ;它可刺激相关产业的发展 ,有利于改善投资环境、分散风险。房地产证券化具有扩大资本市场、增强不动产市场流动性、保持不动产市场稳定性和提高投资者效益性等主要特征。  相似文献   
13.
We describe an image reconstruction problem and the computational difficulties arising in determining the maximum a posteriori (MAP) estimate. Two algorithms for tackling the problem, iterated conditional modes (ICM) and simulated annealing, are usually applied pixel by pixel. The performance of this strategy can be poor, particularly for heavily degraded images, and as a potential improvement Jubb and Jennison (1991) suggest the cascade algorithm in which ICM is initially applied to coarser images formed by blocking squares of pixels. In this paper we attempt to resolve certain criticisms of cascade and present a version of the algorithm extended in definition and implementation. As an illustration we apply our new method to a synthetic aperture radar (SAR) image. We also carry out a study of simulated annealing, with and without cascade, applied to a more tractable minimization problem from which we gain insight into the properties of cascade algorithms.  相似文献   
14.
We propose some estimators of noncentrality parameters which improve upon usual unbiased estimators under quadratic loss. The distributions we consider are the noncentral chi-square and the noncentral F. However, we give more general results for the family of elliptically contoured distributions and propose a robust dominating estimator.  相似文献   
15.
传统的信用风险评估方法仅仅从贷款企业角度来评价商业银行所面临的信用风险,而且评价企业信用风险时,也集中在贷款企业的财务风险评价上,忽略了银行本身存、贷款结构和风险状况对信用风险的影响,造成了评估主体缺位。作为对众多文献的补充,从贷款企业非财务风险因素、银行风险因素和宏观经济环境风险因素三个方面进行了信用风险因素分析,完善了商业银行信用风险评估指标体系。  相似文献   
16.
Low dose risk estimation via simultaneous statistical inferences   总被引:2,自引:0,他引:2  
Summary.  The paper develops and studies simultaneous confidence bounds that are useful for making low dose inferences in quantitative risk analysis. Application is intended for risk assessment studies where human, animal or ecological data are used to set safe low dose levels of a toxic agent, but where study information is limited to high dose levels of the agent. Methods are derived for estimating simultaneous, one-sided, upper confidence limits on risk for end points measured on a continuous scale. From the simultaneous confidence bounds, lower confidence limits on the dose that is associated with a particular risk (often referred to as a bench-mark dose ) are calculated. An important feature of the simultaneous construction is that any inferences that are based on inverting the simultaneous confidence bounds apply automatically to inverse bounds on the bench-mark dose.  相似文献   
17.
在买卖合同中,风险应被限定为标的物因法定免责事由毁损、灭失的不利状态.由于各种风险的存在,风险转移制度显得尤为重要,它直接关系到当事人最根本的利益,因此是买卖合同中最重要的问题.各国对风险转移制度的规定是不同的,主要有合同订立主义、所有人主义及交付主义三种形式.我国买卖合同的风险转移制度采纳交付主义为一般原则,兼采特别法原则.  相似文献   
18.
Summary.  When evaluating potential interventions for cancer prevention, it is necessary to compare benefits and harms. With new study designs, new statistical approaches may be needed to facilitate this comparison. A case in point arose in a proposed genetic substudy of a randomized trial of tamoxifen versus placebo in asymptomatic women who were at high risk for breast cancer. Although the randomized trial showed that tamoxifen substantially reduced the risk of breast cancer, the harms from tamoxifen were serious and some were life threaten-ing. In hopes of finding a subset of women with inherited risk genes who derive greater bene-fits from tamoxifen, we proposed a nested case–control study to test some trial subjects for various genes and new statistical methods to extrapolate benefits and harms to the general population. An important design question is whether or not the study should target common low penetrance genes. Our calculations show that useful results are only likely with rare high penetrance genes.  相似文献   
19.
清官文学的成因是现实苦难的显影、民众诉说苦难心理以及文人拯救苦难情怀三者的合一。通过清官文 学的成因分析表明,清官文学的产生完全是文学自身生态机制作用下的结果。清官文学的合理价值集中表现为 它的现实品格。  相似文献   
20.
Generalized additive models for location, scale and shape   总被引:10,自引:0,他引:10  
Summary.  A general class of statistical models for a univariate response variable is presented which we call the generalized additive model for location, scale and shape (GAMLSS). The model assumes independent observations of the response variable y given the parameters, the explanatory variables and the values of the random effects. The distribution for the response variable in the GAMLSS can be selected from a very general family of distributions including highly skew or kurtotic continuous and discrete distributions. The systematic part of the model is expanded to allow modelling not only of the mean (or location) but also of the other parameters of the distribution of y , as parametric and/or additive nonparametric (smooth) functions of explanatory variables and/or random-effects terms. Maximum (penalized) likelihood estimation is used to fit the (non)parametric models. A Newton–Raphson or Fisher scoring algorithm is used to maximize the (penalized) likelihood. The additive terms in the model are fitted by using a backfitting algorithm. Censored data are easily incorporated into the framework. Five data sets from different fields of application are analysed to emphasize the generality of the GAMLSS class of models.  相似文献   
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