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71.
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.  相似文献   
72.
凌濛初<转运汉巧遇洞庭红>通过对金老汉藏财失财和文若虚随人出海,两次巧遇发财机会陡然暴富故事的描写,反映了明代中叶以后商业发展的具体场景,反映了关于相互需求的贸易原理和资本增殖的思想.通过文若虚形象的塑造,反映了作者经商和为人相统一的思想.从故事可知,明中叶后商业发展已经有了一定的规模和规范,但也还有一些不利于商业贸易更大发展的因素,如储运和金融手段的滞后等.  相似文献   
73.
巩固和发展多种媒体网络教学,积极发展计算机信息技术教育及辅助教学,推动电脑多媒体技术和计算机网络技术在学校教学中的应用。本文探讨了网络课件在教学改革中的重要性和它在教学中的应用以及资料室在制作网络课件过程中的作用。  相似文献   
74.
当语言中的一个新词诞生以后 ,只要表示与之相关的动作变化或状态的动词或形容词没有产生 ,就很可能直接用这个词来表示这种相关的动作变化或状态。因此 ,词的兼类是各种语言或方言、或各个不同时期的同一语言中常见的现象。在语言的发展史上 ,尽可能减少词的兼类现象 ,特别是通过形态变化等手段把兼类的词分化为不同的词 ,还有些词存在活用现象 ,显得很有地方特色。从此角度说 ,客家方言保留着较多的古语痕迹。  相似文献   
75.
This paper is concerned with cases in which patients who have been well established in treatment decide to end it prematurely. In examining the issue among my patients who left against my advice, I isolated in some of them a number of common traits, of which the existence of a long-standing idealizing transference was central. Four of these cases are presented, including two in which the resistance was successfully penetrated and two in which it was not and the patient left treatment. The definition of premature termination is seen in the context of that of a complete analysis.  相似文献   
76.
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.  相似文献   
77.
To ascertain the viability of a project, undertake resource allocation, take part in bidding processes, and other related decisions, modern project management requires forecasting techniques for cost, duration, and performance of a project, not only under normal circumstances, but also under external events that might abruptly change the status quo. We provide a Bayesian framework that provides a global forecast of a project's performance. We aim at predicting the probabilities and impacts of a set of potential scenarios caused by combinations of disruptive events, and using this information to deal with project management issues. To introduce the methodology, we focus on a project's cost, but the ideas equally apply to project duration or performance forecasting. We illustrate our approach with an example based on a real case study involving estimation of the uncertainty in project cost while bidding for a contract.  相似文献   
78.
We propose four different GMM estimators that allow almost consistent estimation of the structural parameters of panel probit models with fixed effects for the case of small Tand large N. The moments used are derived for each period from a first order approximation of the mean of the dependent variable conditional on explanatory variables and on the fixed effect. The estimators differ w.r.t. the choice of instruments and whether they use trimming to reduce the bias or not. In a Monte Carlo study, we compare these estimators with pooled probit and conditional logit estimators for different data generating processes. The results show that the proposed estimators outperform these competitors in several situations.  相似文献   
79.
文学作品是作家本性、人格精神的复现。江西遗民词作为江西遗民词人群个性、心灵之诗意表现 ,其中所表露出的欲挽狂澜于既倒、重整乾坤的雄心与壮志、对自身归属感的积极寻求和对自己所处时空的理性反思、及对社会人生的执著与关注等内容 ,正是这个词人群体在江西独特的地域文化环境中生成的豪逸之气、忠义之心、耿直之性等群体特征的文学表达 ,具有鲜明的地域共性与特色。  相似文献   
80.
This study reports on New Zealand dairy farmers’ access to and use of information as mediated through conditions of risk and trust within the context of their interpersonal social networks. We located participants’ reports of their information use within their perceived environments of trust and risk, following Giddens's [1990. The consequences of modernity. Polity Press, Stanford, CA] typology of trust and risk in pre-modernity and modernity. The research participants were constant users of interpersonal and print information from numerous sources, and monitored their incoming data in the light of strategic needs, reflecting their roles as both farming practitioners and business owners. Socio-spatial knowledge networks (SSKNs) combine individuals’ explanatory cognitive models of information acquisition and use with a micro-geographical analysis of their interpersonal networks. The participants showed characteristics of pre-modern, modern and even post-modern society in respect of their use of complex interactional forms, as well as a blending of individualistic and communitarian practices and concerns in their professional and personal lives.  相似文献   
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