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81.
This paper introduces a double and group acceptance sampling plans based on time truncated lifetimes when the lifetime of an item follows the inverse log-logistic (ILL) distribution with known shape parameter. The operating characteristic function and average sample number (ASN) values of the double acceptance sampling inspection plan are provided. The values of the minimum number of groups and operating characteristic function for various quality levels are obtained for a group acceptance sampling inspection plan. A comparative study between single acceptance sampling inspection plan and double acceptance sampling inspection plan is carried out in terms of sample size. One simulated example and four real-life examples are discussed to show the applicability of the proposed double and group acceptance sampling inspection plans for ILL distributed quality parameters.  相似文献   
82.
It is well-known that classical Tobit estimator of the parameters of the censored regression (CR) model is inefficient in case of non-normal error terms. In this paper, we propose to use the modified maximum likelihood (MML) estimator under the Jones and Faddy''s skew t-error distribution, which covers a wide range of skew and symmetric distributions, for the CR model. The MML estimators, providing an alternative to the Tobit estimator, are explicitly expressed and they are asymptotically equivalent to the maximum likelihood estimator. A simulation study is conducted to compare the efficiencies of the MML estimators with the classical estimators such as the ordinary least squares, Tobit, censored least absolute deviations and symmetrically trimmed least squares estimators. The results of the simulation study show that the MML estimators work well among the others with respect to the root mean square error criterion for the CR model. A real life example is also provided to show the suitability of the MML methodology.  相似文献   
83.
在近代,随着外国侵略势力的到来,中国航运业受到了很大的冲击,中国古老的航运工具———木船受到了排挤。但由于各种原因,在19世纪70—90年代这段时间里中国木船业并没有走向灭亡,而是持续的向前发展。  相似文献   
84.
以系统化思维高质量推进江苏全面深化改革,有利于江苏在全面深化改革中一体贯彻新发展理念、聚力培育发展新动能、统筹推进高质量发展。改革开放40年来,江苏锐意改革、大胆创新、勇立潮头。具体表现为:经济发展体制障碍不断突破,经济综合实力稳步提升;区域协调发展机制逐步构建,区域空间布局日渐优化;社会治理体制创新积极推进,社会治理水平明显提高;生态文明体制改革日益深化,“美丽江苏”建设成效初显。同时,江苏目前在发展方式转变、经济结构优化、增长动力转换等方面仍然存在不少问题和障碍。今后一段时间,江苏应站在更高起点系统谋划和推进各项改革。要着眼走在高质量发展前列,深化经济体制改革;要着眼提高保障和改善民生水平,创新社会治理格局;要着眼经济和社会事业发展全局,完善人才发展制度;要着眼人与大自然是生命共同体,推进生态文明建设。  相似文献   
85.
90后大学生在思想道德方面呈现出独特性:思想观念新锐、张扬、自主、时尚;自我实现意识强,价值取向功利化;危机感强,心理承受能力有限;有较自觉的社会公德意识,能积极弘扬传统美德。这些特征的形成是受社会变革、互联网、家庭教育模式和学校思想政治教育水平等多种因素的影响。加强90后大学生思想道德建设,应以学生为中心,不断创新高校思想道德教育的方法与内容;要发挥家庭教育和社会教育的作用,形成大学生思想道德教育的合力;要加强校园网络文化建设,主动占领网络思想政治教育新阵地。  相似文献   
86.
This paper proposes a new hysteretic vector autoregressive (HVAR) model in which the regime switching may be delayed when the hysteresis variable lies in a hysteresis zone. We integrate an adapted multivariate Student-t distribution from amending the scale mixtures of normal distributions. This HVAR model allows for a higher degree of flexibility in the degrees of freedom for each time series. We use the proposed model to test for a causal relationship between any two target time series. Using posterior odds ratios, we overcome the limitations of the classical approach to multiple testing. Both simulated and real examples herein help illustrate the suggested methods. We apply the proposed HVAR model to investigate the causal relationship between the quarterly growth rates of gross domestic product of United Kingdom and United States. Moreover, we check the pairwise lagged dependence of daily PM2.5 levels in three districts of Taipei.  相似文献   
87.
A smoothed bootstrap method is presented for the purpose of bandwidth selection in nonparametric hazard rate estimation for iid data. In this context, two new bootstrap bandwidth selectors are established based on the exact expression of the bootstrap version of the mean integrated squared error of some approximations of the kernel hazard rate estimator. This is very useful since Monte Carlo approximation is no longer needed for the implementation of the two bootstrap selectors. A simulation study is carried out in order to show the empirical performance of the new bootstrap bandwidths and to compare them with other existing selectors. The methods are illustrated by applying them to a diabetes data set.  相似文献   
88.
Nonresponse is a very common phenomenon in survey sampling. Nonignorable nonresponse – that is, a response mechanism that depends on the values of the variable having nonresponse – is the most difficult type of nonresponse to handle. This article develops a robust estimation approach to estimating equations (EEs) by incorporating the modelling of nonignorably missing data, the generalized method of moments (GMM) method and the imputation of EEs via the observed data rather than the imputed missing values when some responses are subject to nonignorably missingness. Based on a particular semiparametric logistic model for nonignorable missing response, this paper proposes the modified EEs to calculate the conditional expectation under nonignorably missing data. We can apply the GMM to infer the parameters. The advantage of our method is that it replaces the non-parametric kernel-smoothing with a parametric sampling importance resampling (SIR) procedure to avoid nonparametric kernel-smoothing problems with high dimensional covariates. The proposed method is shown to be more robust than some current approaches by the simulations.  相似文献   
89.
In this paper, two new multiple influential observation detection methods, GCD.GSPR and mCD*, are introduced for logistic regression. The proposed diagnostic measures are compared with the generalized difference in fits (GDFFITS) and the generalized squared difference in beta (GSDFBETA), which are multiple influential diagnostics. The simulation study is conducted with one, two and five independent variable logistic regression models. The performance of the diagnostic measures is examined for a single contaminated independent variable for each model and in the case where all the independent variables are contaminated with certain contamination rates and intensity. In addition, the performance of the diagnostic measures is compared in terms of the correct identification rate and swamping rate via a frequently referred to data set in the literature.  相似文献   
90.
In a special paired sample case, Hotelling’s T2 test based on the differences of the paired random vectors is the likelihood ratio test for testing the hypothesis that the paired random vectors have the same mean; with respect to a special group of affine linear transformations it is the uniformly most powerful invariant test for the general alternative of a difference in mean. We present an elementary straightforward proof of this result. The likelihood ratio test for testing the hypothesis that the covariance structure is of the assumed special form is derived and discussed. Applications to real data are given.  相似文献   
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