Variable selection in elliptical linear mixed model

Variable selection in elliptical Linear Mixed Models (LMMs) with a shrinkage penalty function (SPF) is the main scope of this study. SPFs are applied for parameter estimation and variable selection simultaneously. The smoothly clipped absolute deviation penalty (SCAD) is one of the SPFs and it is adapted into the elliptical LMM in this study. The proposed idea is highly applicable to a variety of models which are set up with different distributions such as normal, student-t, Pearson VII, power exponential and so on. Simulation studies and real data example with one of the elliptical distributions show that if the variable selection is also a concern, it is worthwhile to carry on the variable selection and the parameter estimation simultaneously in the elliptical LMM.     

On hysteretic vector autoregressive model with applications

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.     

A new infinitely divisible discrete distribution with applications to count data modeling

A new discrete distribution involving geometric and discrete Pareto as special cases is introduced. The distribution possesses many interesting properties like decreasing hazard rate, zero vertex uni-modality, over-dispersion, infinite divisibility and compound Poisson representation, which makes the proposed distribution well suited for count data modeling. Other issues including closure property under minima, comparison of its distribution tail with other distributions via actuarial indices are discussed. The method of proportion and maximum likelihood method are presented for parameter estimation. Finally the performance of the proposed distribution over other classical and newly proposed infinitely divisible distributions are discussed.     

A new aging concept derived from the increasing convex ordering

In this paper, a comparison between the life distribution of a new unit with that of a used unit in the increasing convex order is made leading to a new class of life distributions which we call “new better than used in convex ordering of second order”. This class includes as subclasses the NBU and the NBUC and is a subclass of the NBUCA class. Preservation properties under convolution, random maxima, mixing and formation of coherent structures are established. Stochastic comparisons of the excess lifetime when the inter-arrival times belong to the NBUC(2) class are developed. Some applications of Poisson shock models and a test of exponentiality against NBUC(2) alternative are presented.     

On approximations via convolution-defined mixture models

An often-cited fact regarding mixing or mixture distributions is that their density functions are able to approximate the density function of any unknown distribution to arbitrary degrees of accuracy, provided that the mixing or mixture distribution is sufficiently complex. This fact is often not made concrete. We investigate and review theorems that provide approximation bounds for mixing distributions. Connections between the approximation bounds of mixing distributions and estimation bounds for the maximum likelihood estimator of finite mixtures of location-scale distributions are reviewed.     

透析实施生育保险制度的局势

从社会学视角对实施生育保险制度的必要性进行探讨,分别从宏观(包括人口转变规律、经济体制改革、提高人口素质的需求三个方面)、中观(包括社会支持网络的变迁、保障女性群体地位、保障企业平等竞争三个方面)和微观层面(包括生育观念的转变、生育的风险性、体现女性的生育价值三个方面)进行层层剖析,说明实施和拓宽生育保险制度势在必行。     

高职院校学生的生育道德观现状与实证研究

研究分别以分层丛集式问卷与子女价值量表对24岁以下的高职学生进行生育道德观的实证分析,旨在探讨生育道德观与未来希望生育子女数及生育挟择的整体关系。结果发现：高职学生以“权力成就”、“亲密情感”、“家庭愉悦”为最主要的认同层面;生育道德观因性剐、交友情况、父母教育程度等成长经验的不同而有所差异;生育道德观中“生育价值”、“生育代价”、“生育挟择”因素对未来希望生育子女数有一定程度的预测力。     

农村未婚青年生殖健康现状及需求研究

本文根据对农村未婚青年生殖健康现状问卷调查和座谈调查的结果,对农村未婚在业青年的生殖健康现状及其对婚前性行为、人工流产的态度进行了分析研究,同时还探讨了农村未婚青年对计划生育服务的需求,最后还就提高农村未婚青年生殖健康水平提出了一些对策性建议。     

“同伴教育”方法在大学生生殖健康教育中的本土化应用——以广州大学为例

同伴教育方法在大学生开展生殖健康教育中的本土化应用非常必要。在设计了本土化教案后,将所有参加实验的学生以班为单位分成对照组、通用教案组、本土化教案组,三组之间进行比较,认为：（1）对照组和通用教案组、本土教案组在性态度、观念、艾滋病常识、行为意向方面有显著差异,证明同伴教育对大学生生殖健康教育行之有效;（2）通用教案组和本土化教案组在学生的态度、观念、知识等方面的效果没有显著差异,但在行为意向方面,本土化教案效果显著优于通用教案。说明本土化设计更有利于对学生的行为指引,在应用同伴教育这一外来方法时,应该结合本地具体情况做必要的修改。