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991.
As the population of Chinese immigrants has been growing rapidly in the United States, it has been understudied on the parenting behaviours as well as the roles parental stress and social support playing in parenting in this group. This study investigated whether parental stress was associated with parenting and whether this relationship was mediated by social support in a sample of 255 Chinese immigrant parents from the Survey of Asian American Families in New York City. Regression analyses with a rich array of control variables found that a higher level of parental stress and the presence of one or more stressors such as unemployment, low income, and low education were positively associated with the use of harsh discipline and parent–child conflicts and negatively associated with positive parenting practices. Social support functioned as a significant mediator in the relationships between parental stress and positive parenting practices but not in the relationships of parental stress with parent–child conflict or the use of harsh discipline.  相似文献   
992.
A need exists to better understand how racial/ethnic minority students' critical consciousness development in response to marginalization may be involved in their educational and career development. We therefore examined the link between critical consciousness development and career decision self-efficacy and career outcome expectations among racial/ethnic minority community college students. Following social cognitive career theory's conceptual pillars, we developed a testable model integrating critical consciousness and social cognitive variables. This model was tested with 135 racially and ethnically diverse community college students. Data analysis included path analyses and tests of model fit using structural equation modeling. Results suggested that (a) higher critical agency is linked to higher career decision self-efficacy and outcome expectations and (b) critical action and reflection have a bidirectional link and predict higher critical agency. Implications for research and practice aiming to close educational and career gaps among racial/ethnic minorities are discussed.  相似文献   
993.
Urban Ecosystems - Critical resources for birds nesting in cities can support populations in spite of the challenges imposed by urbanization, and the identification of such resources can shed light...  相似文献   
994.
柳树滋 《江汉论坛》2006,42(8):56-61
人在脱离了动物界进入社会之后,在人的生物进化中止(基本中止)的地方,开始了人类更加迅速且不断加速的社会进化,实验手段、数学工具和与之相联系的物理想象力始终是人类社会进化的重要条件,它们为人的认识通向感官接触不到的领域开辟着无限深广的道路。科学认识的人类学特征在生物学意义上的不可超越性,决不意味着它在社会学意义上也是不可超越的,只是给这种超越加上了人类学的形式,和必须投影到人类实践平面上的要求。  相似文献   
995.
初冬,中国东北大部分地区已感到寒意。可是,当我们置身在位于大凌河畔的辽宁省朝阳市却全没了寒冷的感觉。11月8日的朝阳,天空湛蓝湛蓝的,大大的太阳照得人格外惬意。“这的天儿真是太好啦!”我们不时地赞叹着。听到我们的感叹,市旅游局小潘说,朝阳这地方日照充足,常年少雨,阳光总是毫无遮挡地洒落在朝阳大地,不然怎么叫朝阳呢!他还认真地补充到,朝阳的气候在全省总是特别的,如果全省阴,俺朝阳这地方准晴;如果说全省有雨,咱这儿顶多是阴天。换个说法,如果朝阳这地方下小雨,那全省大部分地区就得大雨或暴雨了。说话间,我们已来到了号称东北佛…  相似文献   
996.
The traditional classification is based on the assumption that distribution of indicator variable X in one class is homogeneous. However, when data in one class comes from heterogeneous distribution, the likelihood ratio of two classes is not unique. In this paper, we construct the classification via an ambiguity criterion for the case of distribution heterogeneity of X in a single class. The separated historical data in each situation are used to estimate the thresholds respectively. The final boundary is chosen as the maximum and minimum thresholds from all situations. Our approach obtains the minimum ambiguity with a high classification accuracy allowing for a precise decision. In addition, nonparametric estimation of the classification region and theoretical properties are derived. Simulation study and real data analysis are reported to demonstrate the effectiveness of our method.  相似文献   
997.
Graphical representation of survival curves is often used to illustrate associations between exposures and time-to-event outcomes. However, when exposures are time-dependent, calculation of survival probabilities is not straightforward. Our aim was to develop a method to estimate time-dependent survival probabilities and represent them graphically. Cox models with time-dependent indicators to represent state changes were fitted, and survival probabilities were plotted using pre-specified times of state changes. Time-varying hazard ratios for the state change were also explored. The method was applied to data from the Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL). Survival curves showing a ‘split’ at a pre-specified time t allow for the qualitative comparison of survival probabilities between patients with similar baseline covariates who do and do not experience a state change at time t. Time since state change interactions can be visually represented to reflect changing hazard ratios over time. A2ALL study results showed differences in survival probabilities among those who did not receive a transplant, received a living donor transplant, and received a deceased donor transplant. These graphical representations of survival curves with time-dependent indicators improve upon previous methods and allow for clinically meaningful interpretation.  相似文献   
998.
Motivated by a recent tuberculosis (TB) study, this paper is concerned with covariates missing not at random (MNAR) and models the potential intracluster correlation by a frailty. We consider the regression analysis of right‐censored event times from clustered subjects under a Cox proportional hazards frailty model and present the semiparametric maximum likelihood estimator (SPMLE) of the model parameters. An easy‐to‐implement pseudo‐SPMLE is then proposed to accommodate more realistic situations using readily available supplementary information on the missing covariates. Algorithms are provided to compute the estimators and their consistent variance estimators. We demonstrate that both the SPMLE and the pseudo‐SPMLE are consistent and asymptotically normal by the arguments based on the theory of modern empirical processes. The proposed approach is examined numerically via simulation and illustrated with an analysis of the motivating TB study data.  相似文献   
999.
货币当局资产负债表是分析央行行为与货币政策执行情况的一个重要报表。我国货币当局资产负债表科目随着经济金融结构的演变经历了多次调整,本文梳理了我国货币当局资产负债表结构及其演变过程,重新编制1999-2018年的年度可比货币当局资产负债表,通过解析各科目余额及其结构的动态变化特征,揭示统计数据背后的经济逻辑与政策实践、以及重要资产负债科目间的勾稽关系。研究发现:外汇占款和对其他存款性公司的债权是我国货币当局投放基础货币的主要渠道。过去20年中,两种渠道此消彼长反映出我国基础货币投放方式和货币政策调控方式的两次重要转变与创新。在外汇占款大幅增长时期,货币当局曾通过频繁提高法定存款准备金率和发行央行票据回笼过剩流动性。随着国际收支顺差收窄和国内经济由高速增长向高质量发展转变,公开市场操作和创新型再贷款工具将成为货币当局主动投放基础货币的重要渠道。  相似文献   
1000.
随着大数据和网络的不断发展,网络调查越来越广泛,大部分网络调查样本属于非概率样本,难以采用传统的抽样推断理论进行推断,如何解决网络调查样本的推断问题是大数据背景下网络调查发展的迫切需求。本文首次从建模的角度提出了解决该问题的基本思路:一是入样概率的建模推断,可以考虑构建基于机器学习与变量选择的倾向得分模型来估计入样概率推断总体;二是目标变量的建模推断,可以考虑直接对目标变量建立参数、非参数或半参数超总体模型进行估计;三是入样概率与目标变量的双重建模推断,可以考虑进行倾向得分模型与超总体模型的加权估计与混合推断。最后,以基于广义Boosted模型的入样概率建模推断为例演示了具体解决方法。  相似文献   
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