Quick,uncertain, and delayed adults: timing,sequencing and duration of youth-adult transitions in Canada

The transition from youth to adulthood in western societies has become more prolonged and complex as traditional societal norms have lost influence. Using retrospective data from a cohort of 43-year-old Canadians surveyed in 2010 (n?=?405), we mapped the timing, sequencing, and duration of ‘first stage’ youth-adult transitions (leaving home, finishing formal education, obtaining a full-time job) and ‘second stage’ youth-adult transitions (marriage, parenthood, home ownership). Latent profile analysis identified five distinct transition profiles – norm-setters, quick adults, uncertain adults, adult students, and delayed adults – with different amounts and timing of post-secondary educational investment playing an important profile-shaping role. Although youth-adult transitions have become less standardized and more individualized, especially for first stage transitions, these transitions are still quite structured and continue to be affected by gender and family socioeconomic status.     

关于青年研究学科化的思考

本文通过对我国20世纪80年代以来青年研究发展的简要回顾，从知识体系和方法论两方面评述了青年研究的学科化现状。研究认为，青年研究的学科化的标志．应该是独立研究对象及其知识体系以及方法论的确立；不论是青年学还是青年社会学．目前仍然处在科恩所说的前范式阶段。文章从知识体系方面对西方学术成就的借鉴、经验研究方法的规范化，及研究队伍的整合等方面阐述了对青年研究学科化的看法。     

青年社工工作模式探究

本研究从实践研究和理论探索两条路径出发,探究社区青少年社会支持工作模式。研究通过访谈法、问卷法、资料分析法研究了上海市社区青少年心理健康服务的工作现状,验证了从社会支持出发,开展社会工作的意义,并结合理论分析和研究结果,提出社会支持工作模式的建议。     

固定设计异方差非参数回归模型的预测方法

文章针对固定设计下异方差非参数回归模型,考虑了基于多项式样条的三种预测方法,即非外推法、线性外推法和非线性外推法.模拟结果表明非外推预测法的均方根误差(RMSE)和平均绝对误差(MAE)的均值最大,而线性外推法的RMSE和MAE的均值略小于非线性外推法的RMSE和MAE的均值.实证分析结果显示:非外推预测法的平均绝对百分比误差(MAPE)、RMSE和MAE最大,线性外推法的MAPE、RMSE和MAE最小.这表明整体上外推法优于非外推法,而线性外推法是简单可行的.     

Enabling robust assessment of QTc prolongation in early phase clinical trials

Since the implementation of the International Conference on Harmonization (ICH) E14 guideline in 2005, regulators have required a “thorough QTc” (TQT) study for evaluating the effects of investigational drugs on delayed cardiac repolarization as manifested by a prolonged QTc interval. However, TQT studies have increasingly been viewed unfavorably because of their low cost effectiveness. Several researchers have noted that a robust drug concentration‐QTc (conc‐QTc) modeling assessment in early phase development should, in most cases, obviate the need for a subsequent TQT study. In December 2015, ICH released an “E14 Q&As (R3)” document supporting the use of conc‐QTc modeling for regulatory decisions. In this article, we propose a simple improvement of two popular conc‐QTc assessment methods for typical first‐in‐human crossover‐like single ascending dose clinical pharmacology trials. The improvement is achieved, in part, by leveraging routinely encountered (and expected) intrasubject correlation patterns encountered in such trials. A real example involving a single ascending dose and corresponding TQT trial, along with results from a simulation study, illustrate the strong performance of the proposed method. The improved conc‐QTc assessment will further enable highly reliable go/no‐go decisions in early phase clinical development and deliver results that support subsequent TQT study waivers by regulators.     

模糊变权组合预测方法研究

在不确定环境组合预测中,用模糊权重系数更能体现各单项预测方法的客观表现.文章提出一种新的权重系数为三角模糊数的组合预测方法.首先建立以组合预测精确度指数最小为准则的模糊加权组合预测模型,为了避免样本数据中极端值对模型的影响,对模型进行改进,提出带有0-1变量的模糊加权组合预测模型.进一步考虑到单项预测方法在不同时刻的表现有所差异,建立基于诱导有序模糊加权平均(IOFWA)算子的模糊变权组合预测模型,该模型不仅能克服极端值的影响,而且具有更高的预测精确度.并实证验证了该方法的适用性和灵活性.     

Quantile regression for robust estimation and variable selection in partially linear varying-coefficient models

In this paper, we develop a new estimation procedure based on quantile regression for semiparametric partially linear varying-coefficient models. The proposed estimation approach is empirically shown to be much more efficient than the popular least squares estimation method for non-normal error distributions, and almost not lose any efficiency for normal errors. Asymptotic normalities of the proposed estimators for both the parametric and nonparametric parts are established. To achieve sparsity when there exist irrelevant variables in the model, two variable selection procedures based on adaptive penalty are developed to select important parametric covariates as well as significant nonparametric functions. Moreover, both these two variable selection procedures are demonstrated to enjoy the oracle property under some regularity conditions. Some Monte Carlo simulations are conducted to assess the finite sample performance of the proposed estimators, and a real-data example is used to illustrate the application of the proposed methods.     

经济状况、社会保障对居民养老意愿的影响及城乡差异

基于中国综合社会调查(CGSS,2013)数据,分析了经济状况和社会保障对居民养老意愿的影响及城乡差异.研究发现:我国居民养老意愿以自助型及半自助型为主,家庭型次之,社会型最低,农村居民更倾向于家庭型模式;多项Logistic模型的结果显示,经济状况和社会保障因素对居民养老意愿均有显著影响,经济状况和社会保障越好,居民家庭型养老的意愿显著性越低,社会型养老的意愿相对地较高,并且,经济状况和社会保障对城镇居民养老意愿的影响更为显著,对农村居民的影响相对较小.     

城市化与农民工的贡献——后危机时期中国经济增长潜力的思考

金融危机时期农民工就业的调整过程和结果,进一步印证了中国经济发展阶段正在发生的重大变化,即刘易斯转折点已经到来,并显示出与这个新阶段相联系的劳动力市场特征,揭示出经济可持续增长面临的挑战。文章首先论证了农业不再是剩余劳动力的蓄水池,因而农民进城打工已具有不可逆转性。文章还指出,剩余劳动力的减少意味着传统意义上的人口红利将逐渐消失,迫切需要发动经济增长的新引擎,即以农民工市民化为内涵的深度城市化。通过国际比较,文章论证了城市化作为新增长点的意义,对未来城市化的速度进行了判断,并澄清了城市化过程中土地扩张和人口增加的关系,进而论述了推进深度城市化战略的要点——新老居民获得均等的公共服务。     

城镇企业职工基本养老保险基金支付能力预测研究

随着人口老龄化进程的加剧。我国城镇企业职工基本养老保险基金收支出现了巨大缺口并呈现逐步扩大的趋势,导致基金支付能力持续下降。本文应用社会保障精算方法与技术,以社会养老保险现行政策为导向。引入2005年颁布的《国务院关于完善企业职工基本养老保险制度的决定》中新养老金计发办法的经济参数。构建城镇企业职工基本养老保险基金收入与基金支出测算模型,其中以2006年新政策实施年为时间界限。分别构建“老人”、2006年前退休的“中人”（“老中人”）、2006年后退休的“中人”（“新中人”）、“新人”四类群体的基本养老保险基金支出洲算模型。从而推导出城镇企业职工基本养老保险基金支付能力预测精算模型。以期对养老保险基金失衡风险和支竹能力危机进行及时预测。并为社会养老保险政策调整和制度完善提供量化依据。