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101.
For the model considered by Chaturvedi, Pandey and Gupta (1991), two classes of sequential procedures are developed to construct confidence regions (which may be interval, ellipsoidal or spherical) of ‘pre-assigned width and coverage probability’ for the parameters of interest and for the minimum risk point estimation (taking loss to be quadratic plus linear cost of sampling) of the nuisance parameter. Second-Order approximations are derived for the expected sample size, coverage probability and ‘regret’ associated with the two classes of sequential procedures. A simple and direct method of obtaining the asymptotic distribution of the stopping time is provided. By means of examples, it is illustrated that several estimation problems can be tackled with the help of proposed classes of sequential procedures. 相似文献
102.
亚里士多德关于谬误的理论主要载于《工具论》的《辩谬篇》和《前分析篇》中,另外在《修辞学》一书中也有阐述。在《辩谬篇》中,亚里士多德从分析反驳入手对谬误做了定义和界分。《前分析篇》中所体现的特点正是要以明确谬误研究中的逻辑因素。作为逻辑应用理论的现代谬误理论,它的产生和发展表明它不是来和现代形式逻辑竞争的,更不是用来反形式逻辑的,而是作为形式逻辑的一个补充,在不同的研究领域发挥不同的作用。 相似文献
103.
Nicholas G. Hall Joseph Y.‐T. Leung Chung‐Lun Li 《Production and Operations Management》2015,24(8):1248-1265
This study considers a typical scheduling environment that is influenced by the behavioral phenomenon of multitasking. Under multitasking, the processing of a selected job suffers from interruption by other jobs that are available but unfinished. This situation arises in a wide variety of applications; for example, administration, manufacturing, and process and project management. Several classical solution methods for scheduling problems no longer apply in the presence of multitasking. The solvability of any scheduling problem under multitasking is no easier than that of the corresponding classical problem. We develop optimal algorithms for some fundamental and practical single machine scheduling problems with multitasking. For other problems, we show that they are computationally intractable, even though in some cases the corresponding problem in classical scheduling is efficiently solvable. We also study the cost increase and value gained due to multitasking. This analysis informs companies about how much it would be worthwhile to invest in measures to reduce or encourage multitasking. 相似文献
104.
Software packages usually report the results of statistical tests using p-values. Users often interpret these values by comparing them with standard thresholds, for example, 0.1, 1, and 5%, which is sometimes reinforced by a star rating (***, **, and *, respectively). We consider an arbitrary statistical test whose p-value p is not available explicitly, but can be approximated by Monte Carlo samples, for example, by bootstrap or permutation tests. The standard implementation of such tests usually draws a fixed number of samples to approximate p. However, the probability that the exact and the approximated p-value lie on different sides of a threshold (the resampling risk) can be high, particularly for p-values close to a threshold. We present a method to overcome this. We consider a finite set of user-specified intervals that cover [0, 1] and that can be overlapping. We call these p-value buckets. We present algorithms that, with arbitrarily high probability, return a p-value bucket containing p. We prove that for both a bounded resampling risk and a finite runtime, overlapping buckets need to be employed, and that our methods both bound the resampling risk and guarantee a finite runtime for such overlapping buckets. To interpret decisions with overlapping buckets, we propose an extension of the star rating system. We demonstrate that our methods are suitable for use in standard software, including for low p-value thresholds occurring in multiple testing settings, and that they can be computationally more efficient than standard implementations. 相似文献
105.
Qinghua Ji 《统计学通讯:理论与方法》2020,49(7):1537-1560
AbstractIn this article, we propose a penalized local log-likelihood method to locally select the number of components in non parametric finite mixture of regression models via proportion shrinkage method. Mean functions and variance functions are estimated simultaneously. We show that the number of components can be estimated consistently, and further establish asymptotic normality of functional estimates. We use a modified EM algorithm to estimate the unknown functions. Simulations are conducted to demonstrate the performance of the proposed method. We illustrate our method via an empirical analysis of the housing price index data of United States. 相似文献
106.
房连泉 《北京工业大学学报(社会科学版)》2016,16(6):46-53
以探讨构建服务型政府形势下社保经办服务体系改革思路为研究目的。通过实证分析方法,分析了当前社保经办服务建设能力不足和管理体制散乱的突出问题;借鉴国际经验,提出加强顶层设计,结合事业单位分类改革,重塑社保公共服务体系的思路。 相似文献
107.
股利分配政策是上市公司对盈利进行分配或留存的决策问题.在大数据时代运用微软商业智能中的决策树算法,可以对农业上市公司的相关财务数据进行深入挖掘.通过决策树规则进行分析,找出农业上市公司股利分配采购影响因素,为农业上市公司制定现金股利分配股利分配政策提供决策依据,也为商业智能工具在企业决策中的运用提供借鉴. 相似文献
108.
张国钧 《浙江大学学报(人文社会科学版)》2016,2(5):95
天伦、人伦之分最晚始于秦汉,两者在彼此对应中时被混用。从发生角度而言,天伦是天生的伦理,人伦是人为的伦理。天伦、人伦同气分形,共生中国人的伦理永恒、伦理信仰:天伦同气,因血缘而在代代传承中贯通有限生命,内生诚信,分形人伦;人伦基于诚信,为各自目的,从血缘和天伦向外全方位分形为姻缘、情缘、地缘、业缘、神缘、网缘等,使夫妻、朋友及各种职业伦理、社会伦理视需要和可能而及时结合或解散。伦理永恒是中国人的永恒,内化为伦理信仰,与有关因素共生,永葆中华文明生生不息,迥异于世界其他几大文明的命运与其宗教信仰的关系。敦睦伦理,消除伦理危机,关系到国家长治久安、文明生生不息,社会各界责任重大,国家的伦理责任更为重大。 相似文献
109.
针对分水岭算法存在的过分割问题以及泡罩包装药品图像的特点,提出一种改进的分水岭分割算法对泡罩包装的药品进行分割。该方法将形态学重建运算与使用控制标记符的方法相结合,首先对原图像进行开闭重建,根据邻域像素连通性提取重建后图像的局部极大值作为标记,从而抑制其他的局部极小值,然后依据标记对原始的梯度图像进行修正,最后对修改后的梯度图像进行分水岭分割。试验表明,该方法在缺陷药品检测中,可以有效的抑制传统分水岭的过分割,分割效果良好。 相似文献
110.
针对传统基于继电器控制的稳压电源在带负载工作时,档位切换常常伴随火弧现象的问题,设计了一种可广泛
应用于此类稳压电源上的自适应去火弧技术:使用光耦和多级运放完成对零点和电压电流的采样;基于单片机的10量,
实现对继电器的驱动和控制;基于RCC自激震荡原理为系统提供稳定电源;设计了稳压器的完整软件系统程序,并在软
件中应用自适应去火弧算法。实验结果表明:自适应去火弧技术,能够有效地规避火弧现象的产生,并能够根据条件作
出调整。采用自适应去火弧技术的稳压系统达到了设计目标,延长了系统工作寿命。 相似文献