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1.
In a longitudinal, community-based study, adolescent protective factors for those at risk for depression were identified that were associated with resilient outcomes in young adulthood. For those with childhood risk factors for major depression, significant protective factors included family cohesion, positive self appraisals, and good interpersonal relations. Findings may help inform the development of prevention and treatment programs for adolescents vulnerable to depression. Implications for future research and clinical practice are discussed.  相似文献   
2.
江西劳动就业面临的主要问题是劳动力供需矛盾尖锐、劳动力素质偏低。这些问题严重制约着江西经济的健康发展。必须从增加劳动力需求和控制劳动力的供给着手 ,双管齐下 ;同时 ,要把提高劳动力素质贯穿到整个劳动力供需矛盾的解决中去  相似文献   
3.
By approximating the nonparametric component using a regression spline in generalized partial linear models (GPLM), robust generalized estimating equations (GEE), involving bounded score function and leverage-based weighting function, can be used to estimate the regression parameters in GPLM robustly for longitudinal data or clustered data. In this paper, score test statistics are proposed for testing the regression parameters with robustness, and their asymptotic distributions under the null hypothesis and a class of local alternative hypotheses are studied. The proposed score tests reply on the estimation of a smaller model without the testing parameters involved, and perform well in the simulation studies and real data analysis conducted in this paper.  相似文献   
4.
Summary.  The pattern of absenteeism in the downsizing process of companies is a topic in focus in economics and social science. A general question is whether employees who are frequently absent are more likely to be selected to be laid off or in contrast whether employees to be dismissed are more likely to be absent for the remaining time of their working contract. We pursue an empirical and microeconomic investigation of these theses. We analyse longitudinal data that were collected in a German company over several years. We fit a semiparametric transition model based on a mixture Poisson distribution for the days of absenteeism per month. Prediction intervals are considered and the primary focus is on the period of downsizing. The data reveal clear evidence for the hypothesis that employees who are to be laid off are more frequently absent before leaving the company. Interestingly, though, no clear evidence is seen that employees being selected to leave the company are those with a bad absenteeism profile.  相似文献   
5.
罗伯特·弗罗斯特作为二十世纪美国最伟大的诗人之一,其思想和观点在其诗歌艺术创作之中表现出来.本文仅以其诗歌来窥视其观点和思想,为进一步的了解和研究弗罗斯特提供些许研究素材和浅薄的理论认识.  相似文献   
6.
Summary.  In longitudinal studies, missingness of data is often an unavoidable problem. Estimators from the linear mixed effects model assume that missing data are missing at random. However, estimators are biased when this assumption is not met. In the paper, theoretical results for the asymptotic bias are established under non-ignorable drop-out, drop-in and other missing data patterns. The asymptotic bias is large when the drop-out subjects have only one or no observation, especially for slope-related parameters of the linear mixed effects model. In the drop-in case, intercept-related parameter estimators show substantial asymptotic bias when subjects enter late in the study. Eight other missing data patterns are considered and these produce asymptotic biases of a variety of magnitudes.  相似文献   
7.
Summary. Semiparametric mixed models are useful in biometric and econometric applications, especially for longitudinal data. Maximum penalized likelihood estimators (MPLEs) have been shown to work well by Zhang and co-workers for both linear coefficients and nonparametric functions. This paper considers the role of influence diagnostics in the MPLE by extending the case deletion and subject deletion analysis of linear models to accommodate the inclusion of a nonparametric component. We focus on influence measures for the fixed effects and provide formulae that are analogous to those for simpler models and readily computable with the MPLE algorithm. We also establish an equivalence between the case or subject deletion model and a mean shift outlier model from which we derive tests for outliers. The influence diagnostics proposed are illustrated through a longitudinal hormone study on progesterone and a simulated example.  相似文献   
8.
成人教育的有效性探讨   总被引:2,自引:0,他引:2  
成人学习与青年学生不同 ,他们侧重于从经验中学习 ,目的性明确 ,理解能力和分析解决问题的能力较强。但他们的学习也常受制于各种主客观因素 ,存在局限性。要提高成人教育的有效性 ,一要走自学、互学的路子 ,努力建立学习型组织 ,实现知识和经验共享 ;二是改革培训的方式方法 ,提高在教师指导下的培训效果  相似文献   
9.
通守是隋末设置的一个具有特定功能的官职 ,为其他朝代所无 ,主要镇压隋末农民起义。通守的设置 ,既是大业末年政局形势所迫 ,也是隋代加强中央集权、削弱郡守功能的结果。通守尽管为郡级佐官 ,但其实际功能已经取代甚或超越了太守。  相似文献   
10.
国内专利情报研究综述   总被引:7,自引:0,他引:7  
本文从专利情报的作用、分析、工作等六个研究热点对国内的专利情报研究进行了较为全面地总结和概括,并对研究的不足之处提出了自己的看法。  相似文献   
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