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51.
Classical nondecimated wavelet transforms are attractive for many applications. When the data comes from complex or irregular designs, the use of second generation wavelets in nonparametric regression has proved superior to that of classical wavelets. However, the construction of a nondecimated second generation wavelet transform is not obvious. In this paper we propose a new ‘nondecimated’ lifting transform, based on the lifting algorithm which removes one coefficient at a time, and explore its behavior. Our approach also allows for embedding adaptivity in the transform, i.e. wavelet functions can be constructed such that their smoothness adjusts to the local properties of the signal. We address the problem of nonparametric regression and propose an (averaged) estimator obtained by using our nondecimated lifting technique teamed with empirical Bayes shrinkage. Simulations show that our proposed method has higher performance than competing techniques able to work on irregular data. Our construction also opens avenues for generating a ‘best’ representation, which we shall explore.  相似文献   
52.
蒙云龙 《北方论丛》2015,(4):142-145
生态、潮流、反恐、普世等问题已异化为西方意识形态扩张的现代性路径;从全球化趋势的形成和发展、主流意识形态建设的弱化、新媒体发展和普及等方面着力分析西方意识形态扩张现代性路径的诸多原因,加强马克思主义意识形态宣传教育、提升马克思主义意识形态交往的主动权和影响力、促进社会发展和惠民建设等进行应对。  相似文献   
53.
54.
The well-known Wilson and Agresti–Coull confidence intervals for a binomial proportion p are centered around a Bayesian estimator. Using this as a starting point, similarities between frequentist confidence intervals for proportions and Bayesian credible intervals based on low-informative priors are studied using asymptotic expansions. A Bayesian motivation for a large class of frequentist confidence intervals is provided. It is shown that the likelihood ratio interval for p approximates a Bayesian credible interval based on Kerman’s neutral noninformative conjugate prior up to O(n? 1) in the confidence bounds. For the significance level α ? 0.317, the Bayesian interval based on the Jeffreys’ prior is then shown to be a compromise between the likelihood ratio and Wilson intervals. Supplementary materials for this article are available online.  相似文献   
55.
A general procedure is developed for bias-correcting the maximum likelihood estimators (MLEs) of the parameters of Weibull regression model with either complete or right-censored data. Following the bias correction, variance corrections and hence improved t-ratios for model parameters are presented. Potentially improved t-ratios for other reliability-related quantities are also discussed. Simulation results show that the proposed method is effective in correcting the bias of the MLEs, and the resulted t-ratios generally improve over the regular t-ratios.  相似文献   
56.
Generalized variance is a measure of dispersion of multivariate data. Comparison of dispersion of multivariate data is one of the favorite issues for multivariate quality control, generalized homogeneity of multidimensional scatter, etc. In this article, the problem of testing equality of generalized variances of k multivariate normal populations by using the Bartlett's modified likelihood ratio test (BMLRT) is proposed. Simulations to compare the Type I error rate and power of the BMLRT and the likelihood ratio test (LRT) methods are performed. These simulations show that the BMLRT method has a better chi-square approximation under the null hypothesis. Finally, a practical example is given.  相似文献   
57.
Logarithmic general error distribution is an extension of the log-normal distribution. In this paper, the asymptotic expansions of densities of normalized maximum from logarithmic general error distribution are derived under two different kinds of normalized constants. By applying the main results, the higher-order expansions of moments of maxima are established.  相似文献   
58.
犯罪圈的扩张是我国刑事立法的主导方向,现代化的发展、权利的保护是犯罪圈在特定时期不断扩大的主要原因。立法上的犯罪化的内在根据,在于行为具有应受刑罚处罚程度的社会危害性。犯罪圈的扩张应当受到合理限制:遵循刑法的谦抑性原则,考虑新增罪名与其他罪名的关系,考虑国民的感受与认同并理性对待民意,在注重入罪的同时,也应做到及时地出罪。  相似文献   
59.
A simple approximation for the doubly noncentral t-distribution, based upon the Fieller-Geary Theorem (1930) and approximate normality of the square root of the noncentral chi-square variable observed by Patnaik (1949), is developed, This approximation and an Edgeworth series expansion associated with it are evaluated. The simple approximation is seen to be reasonably accurate for most practical purposes.  相似文献   
60.
伦纳德·伍德认为:美国必须为未来战争做好准备,实行国民经济总动员,建立公民军队、平民军事教育体系和预备役军官。他在担任总参谋长期间采取了一系列的措施:提高总参谋部的效率,改革后勤,改组国民警卫队,改革军队编制,开展“普拉茨堡运动”,颁布1916年《国防法》和《扩军法》,为美国参加第一次世界大战做好了准备。  相似文献   
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