Inferences for a Partially Varying Coefficient Model With Endogenous Regressors

In this article, we propose a new class of semiparametric instrumental variable models with partially varying coefficients, in which the structural function has a partially linear form and the impact of endogenous structural variables can vary over different levels of some exogenous variables. We propose a three-step estimation procedure to estimate both functional and constant coefficients. The consistency and asymptotic normality of these proposed estimators are established. Moreover, a generalized F-test is developed to test whether the functional coefficients are of particular parametric forms with some underlying economic intuitions, and furthermore, the limiting distribution of the proposed generalized F-test statistic under the null hypothesis is established. Finally, we illustrate the finite sample performance of our approach with simulations and two real data examples in economics.     

Estimation of the marginal expected shortfall under asymptotic independence

We study the asymptotic behavior of the marginal expected shortfall when the two random variables are asymptotic independent but positively associated, which is modeled by the so-called tail dependent coefficient. We construct an estimator of the marginal expected shortfall, which is shown to be asymptotically normal. The finite sample performance of the estimator is investigated in a small simulation study. The method is also applied to estimate the expected amount of rainfall at a weather station given that there is a once every 100 years rainfall at another weather station nearby.     

政治关联如何影响社会组织有效性？——组织自主性的中介作用和制度支持的调节作用

社会组织领域的政治关联现象日益显著，但政治关联究竟如何影响社会组织有效性，其隐藏的作用机制又是什么？这是学术界尚未明晰的重要课题。针对254家社会组织的问卷调查发现，社会组织政治关联会正向影响组织有效性，这一关系受到组织自主性的中介作用影响。更进一步的研究显示，制度支持能调节上述中介关系。具体而言，当制度支持水平较高时，这一效应将会增强；当制度支持水平较低时，政治关联通过组织自主性间接影响组织有效性的效应就会减弱。这一发现，一方面增进了我们对社会组织政治关联的理解，另一方面也为提升社会组织有效性的理论和实践提供了重要启示。     

Chinese Language Media in the United States: Immigration and Assimilation in American Life

Qualitative Sociology - The upsurge of Chinese language media—publications, radio, television, and the Internet—mirrors the linguistic, cultural, and socioeconomic diversity of the...     

4×100米接力跑组队与训练方法

本文通过对4×100米接力跑的技术特点的分析,指出了合理选拔队员组成接力队,并运用合理的训 练方法,使运动员熟练掌握传接棒技术,提高每个队员的单跑能力,进而提高4×100米接力跑的成绩。     

Monitoring the parameter changes in general ARIMA time series models

We propose methods for monitoring the residuals of a fitted ARIMA or an autoregressive fractionally integrated moving average (ARFIMA) model in order to detect changes of the parameters in that model. We extend the procedures of Box & Ramirez (1992) and Ramirez (1992) and allow the differencing parameter, d to be fractional or integer. Test statistics are approximated by Wiener processes. We carry out simulations and also apply our method to several real time series. The results show that our method is effective for monitoring all parameters in ARFIMA models.     

R12在水平管内流动沸腾换热实验研究

本文对R12在水平管内流动沸腾换热特性作了实验研究。实验结果表明,管内流动沸腾换热与单相对流换热一样,存在热进口效应,国外早期的实验数据由于未能考虑热进口效应而偏大。实验结果还表明,水平流动沸腾周向不均匀换热主要受流动结构影响;截面平均换热系数则与质量流速、热流密度、质量干度和蒸发压力密切相关。分析实验数据证实,流动沸腾换热是由气泡产生而引起的流动充分发展核态沸腾和双相对流蒸发两部分组成的。本文的实验数据与国外已有的换热关系式能较好吻合。     

新一代的解构与重建：香港经验

本文分析了新一代在二十一世纪所面临的三大解构危机:失连、失力和失位,并结合香港的长期研究与实践,分享帮助新一代重建结连、抗逆力与参与的经验.     

成都市城乡文盲率新趋势--以金牛区为个案进行分析

对成都市金牛区最新的五普数据与四普数据进行对比分析 ,发现城镇文盲率高于乡村文盲率0 .4 7个百分点。本文对此现象产生的原因予以详细阐述。     

再论用马克思主义世界观培养创新精神

科学技术创新和理论创新过程 ,是人类对物质世界和社会发展变化及其运动规律的认识深化过程 ,是一个永无止境地由浅入深 ,向更深层次延伸和向更宽广度伸展的过程。客观物质世界和人类社会发展变化及其运动是无限的 ,人们主观世界所达到的科学技术和理论认识都是有限的 ,都不是绝对的。与时俱进 ,开拓创新 ,是自然界和人类社会发展运动的内在要求。科学实验是发现科学、创新科学的必要手段。支持创新 ,允许失败。在科学技术创新过程中有失败的人 ,未必不是成功者 ;不求探索、没有失败的人 ,未必就是成功者。现代化大生产、现代化科学实验 ,是一个创新科学技术和理论的广阔天地。爱国并始终把国家的繁荣昌盛、民族的兴旺发达视为自己毕生追求 ,是我国历代科学家所共有的崇高品格 ,是中华民族的伟大民族精神的体现