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21.
阿奎那关于个别感觉与普遍理性表征的理论是其对理智之非物质性论证的关键部分,但这一理论受到司各特、奥卡姆及布里丹等后来者的批评。然而,这些批评其实都不能成立。阿奎那的论证并不像罗伯特·帕斯纳奥对他的诘难中所说的那样,犯了从一个表征的语义内容推出此表征之本体论属性的“内容谬误”。此外,由布里丹本人的评论可以看出,布里丹实际上不得不接受他所批评的阿奎那论证所蕴含的主要内容。  相似文献   
22.
Kleinbaum (1973) developed a generalized growth curve model for analyzing incomplete longitudinal data. In this paper the small sample properties of several related test statistics are investigated via Monte Carlo techniques. The covariance matrix is estimated by each of three non-iterative methods. The null and non-null distributions of these test statistics are examined.  相似文献   
23.
Nonparametric models with jump points have been considered by many researchers. However, most existing methods based on least squares or likelihood are sensitive when there are outliers or the error distribution is heavy tailed. In this article, a local piecewise-modal method is proposed to estimate the regression function with jump points in nonparametric models, and a piecewise-modal EM algorithm is introduced to estimate the proposed estimator. Under some regular conditions, the large-sample theory is established for the proposed estimators. Several simulations are presented to evaluate the performances of the proposed method, which shows that the proposed estimator is more efficient than the local piecewise-polynomial regression estimator in the presence of outliers or heavy tail error distribution. What is more, the proposed procedure is asymptotically equivalent to the local piecewise-polynomial regression estimator under the assumption that the error distribution is a Gaussian distribution. The proposed method is further illustrated via the sea-level pressures.  相似文献   
24.
Bayesian acceptance sampling plans, which utilize prior information on the process variation, can be employed as an alternative to conventional types of plans for taking decisions on the disposition of submitted lots. A special type of double sampling inspection plans by attributes with small acceptance numbers using Bayesian methodology is presented in this paper emphasizing its significance over small acceptance number single sampling plans. The procedures for designing such sampling plans for specified degree of discrimination which would ensure protection to the producer and consumer are discussed with illustrations under the conditions for the application of gamma-Poisson distribution.  相似文献   
25.
In this paper, a variable repetitive group sampling plans based on one-sided process capability indices is proposed to deal with lot sentencing for one-sided specifications. The parameters of the proposed plans are tabulated for some combinations of acceptance quality levels with commonly used producer's risk and consumer's risk. The efficiency of the proposed plan is compared with the Pearn and Wu [Critical acceptance values and sample sizes of a variables sampling plan for very low fraction of defectives. Omega – Int J Manag Sci. 2006;34(1):90–101] plan in terms of sample size and the power curve. One example is given to illustrate the proposed methodology.  相似文献   
26.
The receiver operating characteristic (ROC) curve is one of the most commonly used methods to compare the diagnostic performance of two or more laboratory or diagnostic tests. In this paper, we propose semi-empirical likelihood based confidence intervals for ROC curves of two populations, where one population is parametric and the other one is non-parametric and both have missing data. After imputing missing values, we derive the semi-empirical likelihood ratio statistic and the corresponding likelihood equations. It is shown that the log-semi-empirical likelihood ratio statistic is asymptotically scaled chi-squared. The estimating equations are solved simultaneously to obtain the estimated lower and upper bounds of semi-empirical likelihood confidence intervals. We conduct extensive simulation studies to evaluate the finite sample performance of the proposed empirical likelihood confidence intervals with various sample sizes and different missing probabilities.  相似文献   
27.
It is well known that the testing of zero variance components is a non-standard problem since the null hypothesis is on the boundary of the parameter space. The usual asymptotic chi-square distribution of the likelihood ratio and score statistics under the null does not necessarily hold because of this null hypothesis. To circumvent this difficulty in balanced linear growth curve models, we introduce an appropriate test statistic and suggest a permutation procedure to approximate its finite-sample distribution. The proposed test alleviates the necessity of any distributional assumptions for the random effects and errors and can easily be applied for testing multiple variance components. Our simulation studies show that the proposed test has Type I error rate close to the nominal level. The power of the proposed test is also compared with the likelihood ratio test in the simulations. An application on data from an orthodontic study is presented and discussed.  相似文献   
28.
湖南省实施发展学前教育三年行动计划效果明显,学前教育机构总数、在园幼儿数、学前三年毛入学率显著增加。与经济发达省份对比,湖南省学前教育普及水平还比较落后,城镇学前教育普及水平明显高于农村地区,县域之间学前教育普及水平差距明显。湖南省普及学前教育面临的主要问题是:政府主导作用发挥不够、农村学前教育普及水平落后、学前教育基础建设不足、普及学前教育路径不畅。推进湖南学前教育持续普及,需要构建学前教育公共服务体系,大力扶持农村学前教育,建立学前教育的保障体系,优化学前教育普及模式。  相似文献   
29.
老年人、青年人、儿童多代合居的家庭,因生活方式的差异致使传统的卫浴空间设计显现出诸多问题。在空间规划、设施配置、氛围营造三个方面引入通用设计理念,合理设计卫浴空间使合居家庭的生活更加融洽。  相似文献   
30.
对一种手动爬楼梯轮椅的运动过程进行了分析。在各部件不与楼梯台阶相干涉的条件下,计算出了车辆质心位置的座标值,并依此绘出质心的位移轨迹曲线。计算了轮椅在上爬楼梯时运动期的中间段质心的速度、加速度以及人的操纵力值。为进一步进行动力学分析和轮椅的改进设计提供了依据。  相似文献   
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