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81.
Xiong Cai  Yiying Zhang 《Statistics》2017,51(3):615-626
In this paper, we compare the hazard rate functions of the second-order statistics arising from two sets of independent multiple-outlier proportional hazard rates (PHR) samples. It is proved that the submajorization order between the sample size vectors together with the supermajorization order between the hazard rate vectors imply the hazard rate ordering between the corresponding second-order statistics from multiple-outlier PHR random variables. The results established here provide theoretical guidance both for the winner's price for the bid in the second-price reverse auction in auction theory and fail-safe system design in reliability. Some numerical examples are also provided for illustration.  相似文献   
82.
Methods are proposed to combine several individual classifiers in order to develop more accurate classification rules. The proposed algorithm uses Rademacher–Walsh polynomials to combine M (≥2) individual classifiers in a nonlinear way. The resulting classifier is optimal in the sense that its misclassification error rate is always less than, or equal to, that of each constituent classifier. A number of numerical examples (based on both real and simulated data) are also given. These examples demonstrate some new, and far-reaching, benefits of working with combined classifiers.  相似文献   
83.
The hazard rate (HR) and mean residual lifetime are two of the most practical and best-known functions in biometry, reliability, statistics and life testing. Recently, the reversed HR function is found to have interesting properties useful in additional areas such as censored data and forensic science. For these three biometric functions, we propose testing methods that they take on a known functional form against that they dominate or are dominated by this known form. This goodness-of-fit-type testing is wider in applications and more interesting than the long-standing testing procedures for exponentiality against the monotonicity of these functions or even the change point problems. This is so since we can test against any choice of the survival distribution and not just exponentiality. For this general testing, we present easy to implement tests and generalize them into classes of statistics that could lead to more powerful and efficient testing.  相似文献   
84.
中国房地产税制:存在问题与改革设想   总被引:1,自引:0,他引:1  
在现代市场经济条件下,房地产税制具有十分重要的功能。现阶段中国房地产税制存在房地产税收功能分散,房地产税种设置交叉重叠现象突出,计税依据不符合国际惯例,房地产保有环节税负偏轻和房地产税权分布结构不合理等问题。中国房地产税制改革已进入基础性制度建设阶段,必须按照"宽税基、简税种、低税率"的原则,实现房地产开发流转环节税收为主向房地产保有环节税收为主的房地产税制转型,去土地财政化,这就要适时开征房产税。开征房产税可以分两步走,近期对居民新购商品房超免税标准部分征收房产税,中长期覆盖到居民已购存量房地产。  相似文献   
85.
环境的公共性和检察权的公益性决定了检察机关有义务介入环境公益诉讼。关于检察机关在环境公益诉讼中的法律地位问题,学者们提出了不同的主张。在环境公益诉讼中检察机关只以一种身份出现的观点是片面的,环境公益诉讼的多样性决定了检察机关介入环境公益诉讼法律地位的多样性。在环境公益诉讼中检察机关的恰当角色是,根据案件的类型不同,分别以支持起诉人身份、准原告人身份、公益代表人身份出现,角色混乱将会造成事与愿违的效果。  相似文献   
86.
传承传统重义轻利观念的大学教育,对学生的财富意识具有极大的压抑作用。改革开放以来,一部分人陷入拜金主义的泥潭,一部分人则保持着"饿死事小失节事大"的极端思想。调查的结果令人担忧,大学生财商整体水平较低。对大学生进行财商教育,是实现教育"使人更幸福地生活"目的之必然要求。  相似文献   
87.
本案例中,大学的规章制度与组织结构规定了参与旧房改造项目相关决策的群体和机构以及做出相关决策所需要的步骤与程序,也规定了不同群体在这一决策过程中的不同地位和可能拥有的资源,甚至是他们的决策倾向;旧房改造项目的冲突根源在于计划经济体制向市场经济体制转型过程中大学内部出现的不同群体的利益分化,但值得注意的是,这些不同群体的利益冲突却是以质疑相关环节上决策者行为的合法性为中心展开的,而关于合法性的争议则更多地涉及了对相关行为的价值意义的解释。  相似文献   
88.
Lack of data on daily inhalation rate and activity of children has been an issue in health risk assessment of air pollutants. This study aimed to obtain the daily inhalation rate and intensity and frequency of physical activity in relation to the environment in Japanese preschool children. Children aged four–six years (n= 138) in the suburbs of Tokyo participated in this study, which involved three days' continuous monitoring of physical activity using a tri‐axial accelerometer and parent's completion of a time/location diary during daily life. The estimated three‐day mean daily inhalation rate (body temperature, pressure, saturated with water vapor) was 9.9 ± 1.6 m3/day (0.52 ± 0.09 m3/kg/day). The current daily inhalation rate value of 0.580 m3/kg/day proposed for use in health risk assessment in Japan is confirmed to be valid to calculate central value of inhaled dose of air pollutants in five‐ to six‐year‐old children. However, the 95th percentile daily inhalation rate of 0.83 m3/kg/day based on measurement for five‐year‐old children is recommended to be used to provide an upper bound estimate of exposure that ensure the protection of all five‐ to six‐year‐old children from the health risk of air pollutants. Children spent the majority of their time in sedentary and light level of physical activity (LPA) when indoors, while 85% of their time when outdoors was spent in LPA and moderate‐to‐vigorous physical activity. The results suggest the need to consider variability of minute respiratory ventilation rate according to the environment for more refined short‐term health risk assessment.  相似文献   
89.
The concept of self-interest remains underdeveloped in sociology although central to economics. Recent methodological and social trends render sociological indifference to the concept untenable. The term has enjoyed historical predominance in the West since the sixteenth century. While it is seen in modern economics as a singular motivating force, Adam Smith regarded self-interest in economic action as necessarily moderated by sympathy. In addition to its problematic economic conceptualization self-interest has an experiential basis in unequal power relations. An alternative to the concept of self-interest is presented by Amartya Sen in his account of commitment; its inconsistencies, however, render Sen's statement unsatisfactory. Differences between present and future interests indicate that the distinction between self-interested and other-interested action is not sustainable.  相似文献   
90.
In this article, we calibrate the Vasicek interest rate model under the risk neutral measure by learning the model parameters using Gaussian processes for machine learning regression. The calibration is done by maximizing the likelihood of zero coupon bond log prices, using mean and covariance functions computed analytically, as well as likelihood derivatives with respect to the parameters. The maximization method used is the conjugate gradients. The only prices needed for calibration are zero coupon bond prices and the parameters are directly obtained in the arbitrage free risk neutral measure.  相似文献   
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