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171.
This article presents a novel and simple approach to the estimation of a marginal likelihood, in a Bayesian context. The estimate is based on a Markov chain output which provides samples from the posterior distribution and an additional latent variable. It is the mean of this latent variable which provides the estimate for the value of the marginal likelihood.  相似文献   
172.
When incomplete repeated failure times are collected from a large number of independent individuals, interest is focused primarily on the consistent and efficient estimation of the effects of the associated covariates on the failure times. Since repeated failure times are likely to be correlated, it is important to exploit the correlation structure of the failure data in order to obtain such consistent and efficient estimates. However, it may be difficult to specify an appropriate correlation structure for a real life data set. We propose a robust correlation structure that can be used irrespective of the true correlation structure. This structure is used in constructing an estimating equation for the hazard ratio parameter, under the assumption that the number of repeated failure times for an individual is random. The consistency and efficiency of the estimates is examined through a simulation study, where we consider failure times that marginally follow an exponential distribution and a Poisson distribution is assumed for the random number of repeated failure times. We conclude by using the proposed method to analyze a bladder cancer dataset.  相似文献   
173.
This article describes the differential mortality of Argentina’s disability pension beneficiaries during the 2015–16 period, based on National Social Security Administration (Administración Nacional de la Seguridad Social – ANSES) payment records. It compares data for those with an assessed disability with overall population data, as well as with available international data (from Canada, Chile, Mexico, and the United States of America). In addition to breaking down mortality rates for people with disabilities by age and sex, it also factors in duration of benefit, establishing an inverse correlation between benefit duration and mortality.  相似文献   
174.
The use of table saws in the United States is associated with approximately 28,000 emergency department (ED) visits and 2,000 cases of finger amputation per year. This article provides a quantitative estimate of the economic benefits of automatic protection systems that could be designed into new table saw products. Benefits are defined as reduced health‐care costs, enhanced production at work, and diminished pain and suffering. The present value of the benefits of automatic protection over the life of the table saw are interpreted as the switch‐point cost value, the maximum investment in automatic protection that can be justified by benefit‐cost comparison. Using two alternative methods for monetizing pain and suffering, the study finds switch‐point cost values of $753 and $561 per saw. These point estimates are sensitive to the values of inputs, especially the average cost of injury. The various switch‐point cost values are substantially higher than rough estimates of the incremental cost of automatic protection systems. Uncertainties and future research needs are discussed.  相似文献   
175.
Access management, which systematically limits opportunities for egress and ingress of vehicles to highway lanes, is critical to protect trillions of dollars of current investment in transportation. This article addresses allocating resources for access management with incomplete and partially relevant data on crash rates, travel speeds, and other factors. While access management can be effective to avoid crashes, reduce travel times, and increase route capacities, the literature suggests a need for performance metrics to guide investments in resource allocation across large corridor networks and several time horizons. In this article, we describe a quantitative decision model to support an access management program via risk‐cost‐benefit analysis under data uncertainties from diverse sources of data and expertise. The approach quantifies potential benefits, including safety improvement and travel time savings, and costs of access management through functional relationships of input parameters including crash rates, corridor access point densities, and traffic volumes. Parameter uncertainties, which vary across locales and experts, are addressed via numerical interval analyses. This approach is demonstrated at several geographic scales across 7,000 kilometers of highways in a geographic region and several subregions. The demonstration prioritizes route segments that would benefit from risk management, including (i) additional data or elicitation, (ii) right‐of‐way purchases, (iii) restriction or closing of access points, (iv) new alignments, (v) developer proffers, and (vi) etc. The approach ought to be of wide interest to analysts, planners, policymakers, and stakeholders who rely on heterogeneous data and expertise for risk management.  相似文献   
176.
基于重庆、湖北、浙江三省市城镇居民的入户抽样调查数据,分析我国公众对转基因水稻的接受态度及区域差异。研究发现,转基因水稻的接受态度存在区域差异,湖北、重庆分样本的接受度明显高于浙江;从影响因素来看,总体上城镇居民转基因水稻接受态度主要是受粮食安全收益感知、对科技系统的信任程度、健康与环境风险感知等因素影响,分样本比较显示浙江城镇居民的态度较之重庆、湖北受到更多风险感知因素的影响。基于此,提出了农业科技风险管理中注重粮食安全、培育科学自生系统等建议。  相似文献   
177.
178.
对河北省学术期刊生存与发展的思考   总被引:3,自引:0,他引:3  
一份学术刊物仅仅发行百多份,其科研成果无法向社会推广传播,无法面对日益激烈的市场竞争。经过调查认为,制约学术期刊生存与发展的因素主要有:缺乏经费;人才流失;知识老化。针对上述情况,提出了对策。  相似文献   
179.
社会主义市场经济条件下的道德建设问题,是一个事关社会主义现代化建设成败的大问题。邓小平同志从时代发展的需要出发,在坚持马克思主义基本道德原则的基础上,创造性地研究解决了社会主义市场经济条件下的义利关系、利益关系、公平与效率关系及人的全面发展问题。其思想对我国今后的道德建设奠定了理论基础并制定了实践方针  相似文献   
180.
我国当前的工业化和城市化浪潮使失地农民数量急剧增加,在此过程中,失地农民利益受损,陷入失地又失业的困境,抵御风险能力急剧下降,其中一个重要的原因就在于农村公共管理制度的缺失。  相似文献   
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