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21.
We investigate the asymptotic behaviour of binned kernel density estimators for dependent and locally non-stationary random fields converging to stationary random fields. We focus on the study of the bias and the asymptotic normality of the estimators. A simulation experiment conducted shows that both the kernel density estimator and the binned kernel density estimator have the same behavior and both estimate accurately the true density when the number of fields increases. We apply our results to the 2002 incidence rates of tuberculosis in the departments of France. 相似文献
22.
Shwetank Lall Seema Jaggi Cini Varghese Arpan Bhowmik 《Journal of Statistical Computation and Simulation》2018,88(6):1191-1199
In this paper, locally D-optimal saturated designs for a logistic model with one and two continuous input variables have been constructed by modifying the famous Fedorov exchange algorithm. A saturated design not only ensures the minimum number of runs in the design but also simplifies the row exchange computation. The basic idea is to exchange a design point with a point from the design space. The algorithm performs the best row exchange between design points and points form a candidate set representing the design space. Naturally, the resultant designs depend on the candidate set. For gain in precision, intuitively a candidate set with a larger number of points and the low discrepancy is desirable, but it increases the computational cost. Apart from the modification in row exchange computation, we propose implementing the algorithm in two stages. Initially, construct a design with a candidate set of affordable size and then later generate a new candidate set around the points of design searched in the former stage. In order to validate the optimality of constructed designs, we have used the general equivalence theorem. Algorithms for the construction of optimal designs have been implemented by developing suitable codes in R. 相似文献
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自20世纪70年代吉伯德-萨特思韦特防策略不可能性定理确立后,引起了数学、经济学、计算机科学和哲学等诸多领域中学者的广泛关注。然而,在国内外文献中,对吉伯德-萨特思韦特防策略不可能性定理的逻辑研究还比较少。基于此,借助公理化的方法探讨吉伯德-萨特思韦特防策略不可能性定理,并形式化地给出定理的内容和证明,力图把精细的逻辑推理应用于复杂的过程分析中,使防策略投票这一过程形式化、清晰化,以期能指导人们进行合理、有效的决策活动。 相似文献
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Two-unit warm standby systems have been elaborately dealt within the literature. However, the study of standby systems with more than two units, though very relevant in state-of-the-art practical situations, has received little attention because of mathematical intricacies involved in analyzing them. Also, such systems have been studied assuming: (i) the lifetime or repair time of the units to be exponential, or (ii) the lifetime and repair time to be independent. The present contribution is an improvement in the state-of-the-art in the sense that three-unit warm standby system with dependent structure is shown to be capable of comprehensive analysis. 相似文献
27.
学生综合素质测评体系的完善对有效实施大学生综合素质测评工作以及指导大学生健康发展有重要意义,其中,学生综合素质测评体系的关键在于学分绩点与综合素质测评的换算模型的转化。通过分析高校现行学分绩点测评公式,发现其存在的主要缺陷是转化公式不满足统计学原理,并指出学分绩点测评的换算公式应建立在对特定学生群体特征参数群数值分析的基础上。以西南石油大学某专业学生某学年的成绩分布数据进行验证,采取统计原理、常数变异法和不动点原理进行建模,利用求导方法对学分绩点测评中的特征参数群进行层次划分,然后对每段划分积分,通过归一化来确定变异项,得出新的换算模型。结果表明新模型能更好地反映学生的学习成绩在综合素质测评中的地位。 相似文献
28.
This article discusses how analyst's or expert's beliefs on the credibility and quality of models can be assessed and incorporated into the uncertainty assessment of an unknown of interest. The proposed methodology is a specialization of the Bayesian framework for the assessment of model uncertainty presented in an earlier paper. This formalism treats models as sources of information in assessing the uncertainty of an unknown, and it allows the use of predictions from multiple models as well as experimental validation data about the models’ performances. In this article, the methodology is extended to incorporate additional types of information about the model, namely, subjective information in terms of credibility of the model and its applicability when it is used outside its intended domain of application. An example in the context of fire risk modeling is also provided. 相似文献
29.
张晓利 《江苏石油化工学院学报(哲学社会科学版)》2014,(3):82-85
弃“席”而“坐”居住方式的重大变革是中国古典家具“分”与“融”的主要根源。以楚式家具、宋式家具、明清家具为代表,在矮型家具向高型家具的演变进程中,家具突显出在功能、阶级风格上的“分离”和以消除与居住方式的分歧为目的的式样上的“融合”。其中的“分”与“融”,对现代设计中如何把握产品功能、设计元素、品牌文化的“取”“舍”尺度问题具有重要启示。 相似文献
30.
Dankmar Böhing 《Statistics》2013,47(4):487-495
Tn optimal experimental design theory there are well-known situations, in which additional constraints are implied to the design set. These constraints destroy in general the simplex structure of the set of feasible points of the design set. Thus the available iteration procedures for the unrestricted case are no longer applicable. In this paper a penalty approach is suggested which transforms the restricted problem to the unrestricted case and allows the application of well-known algorithms such as the Fedorov-Wynn-type or the projected gradient procedure. 相似文献