Loss functions for estimation of extrema with an application to disease mapping

It is often of interest to find the maximum or near maxima among a set of vector‐valued parameters in a statistical model; in the case of disease mapping, for example, these correspond to relative‐risk “hotspots” where public‐health intervention may be needed. The general problem is one of estimating nonlinear functions of the ensemble of relative risks, but biased estimates result if posterior means are simply substituted into these nonlinear functions. The authors obtain better estimates of extrema from a new, weighted ranks squared error loss function. The derivation of these Bayes estimators assumes a hidden‐Markov random‐field model for relative risks, and their behaviour is illustrated with real and simulated data.     

论绿色消费方式的形成

绿色消费是可持续发展的消费方式,它的形成对人类可持续发展具有重要意义。论文主张从建立可持续发展的消费价值观,建立合理的财富分配秩序,调整经济结构和生产方式,并依靠科技进步和发挥政府的主导作用来促进绿色消费的形成。     

激活沉淀资源 加快贵州发展

目前我国社会中存在生产要素闲置状况 ,而且这种状况有加剧的趋势。党的十六大提出全新的价值理论 ,并在这一理论指导下解决该类问题 :提出激活闲置资源 ,加快经济社会稳定发展的建议和措施     

科学配置合并组建高校的文献信息资源

组建高校面临着全校文献信息资源的重组和合理配置 ,针对合并组建高校的文献信息资源重组和配置采取正确的对策和措施 ,发挥数字化文献信息资源的作用 ,从而充分发挥合并组建高校文献信息资源的整体效益     

新城市社会学视域下我国当代城市空间生产的特征

以新城市社会学理论的新马克思主义政治经济学来分析我国当代城市空间生产的特征,是一个新的视域。转型时期我国当代城市的空间生产呈现出新的特征,表现为资本、技术——工业理性刺激着城市的快速扩张,出现环境污染、建设破坏、文化破坏等社会问题,城市空间的生产是不同社会群体对空间的角逐过程和结果,反映着政府、公共领域与个人的边界。城市空间的生产能动地、全面地反映着资本、权力、财富、社会地位、利益等社会关系的生产。     

On Rates of Convergence for Bayesian Density Estimation

Abstract.  We consider the problem of estimating a compactly supported density taking a Bayesian nonparametric approach. We define a Dirichlet mixture prior that, while selecting piecewise constant densities, has full support on the Hellinger metric space of all commonly dominated probability measures on a known bounded interval. We derive pointwise rates of convergence for the posterior expected density by studying the speed at which the posterior mass accumulates on shrinking Hellinger neighbourhoods of the sampling density. If the data are sampled from a strictly positive, α -Hölderian density, with α  ∈ ( 0,1] , then the optimal convergence rate n^{− α / (2 α +1)} is obtained up to a logarithmic factor. Smoothing histograms by polygons, a continuous piecewise linear estimator is obtained that for twice continuously differentiable, strictly positive densities satisfying boundary conditions attains a rate comparable up to a logarithmic factor to the convergence rate n ^−4/5 for integrated mean squared error of kernel type density estimators.     

A bayesian estimator for the dependence function of a bivariate extreme‐value distribution

Any continuous bivariate distribution can be expressed in terms of its margins and a unique copula. In the case of extreme‐value distributions, the copula is characterized by a dependence function while each margin depends on three parameters. The authors propose a Bayesian approach for the simultaneous estimation of the dependence function and the parameters defining the margins. They describe a nonparametric model for the dependence function and a reversible jump Markov chain Monte Carlo algorithm for the computation of the Bayesian estimator. They show through simulations that their estimator has a smaller mean integrated squared error than classical nonparametric estimators, especially in small samples. They illustrate their approach on a hydrological data set.     

论产业化时代的精神文化生产

文章结合十六大文件的深入学习,透视了当代文化产业遭遇的各种现实尴尬,并对一系列相关的理论与实践问题展开了学理性追问,包括当代西方马克思主义美学和19世纪的传统马克思主义美学的相关论述,着重分析了当代文化生产的四个重要特征:即不间断的意识形态再生产的商品化特征,以符号作手段以传媒为载体进行市场流通的特征,个性化与标准化及原创性与复制性的综合过程特征,在多次体验消费中获得价值增值的特征。     

水资源跨流域配置的经济学分析

由于我国水资源空间分布不均匀的突出特点 ,大型跨流域调水工程已经成为我国国民经济可持续发展的重要支撑。文章从水资源的经济特点出发 ,结合南水北调中线工程 ,对水资源跨流域配置的市场供求、成本收益等资源经济学问题进行了分析 ,并对社会主义市场经济条件下水资源跨流域配置的利益分配机制进行了探讨     

A note on LeCam’s bound for the distance between the Poisson binomial and the Poisson distribution

n possibly different success probabilities p ₁, p ₂, ..., p _n is frequently approximated by a Poisson distribution with parameter λ = p ₁ + p ₂ + ... + p _n . LeCam's bound p ² ₁ + p ² ₂ + ... + p _n ² for the total variation distance between both distributions is particularly useful provided the success probabilities are small. The paper presents an improved version of LeCam's bound if a generalized d-dimensional Poisson binomial distribution is to be approximated by a compound Poisson distribution. Received: May 10, 2000; revised version: January 15, 2001