从群体遗传的DNA线索看东乡族族源问题

DNA分析技术的发展为进行民族识别和分析民族起源、迁徙、流动、融合提供了新手段。本文在国内外首次应用D13S317基因座第 11号等位基因频率指标 ,计算了东乡族群体遗传动态数据。结果发现 ,东乡族和回族遗传距离很近 ,且东乡族中具有白种人血缘混杂。结合其他有关资料 ,我们认为东乡族的起源与元代蒙古军带来的中亚工匠、签军有关 ,亦与当地蒙古族、回族、藏族人群的融合有关。本文的研究结果可以为民族研究提供群体遗传方面的线索     

Alternative estimation methods for identifying contagion effects in dynamic social networks: A latent-space adjusted approach

Contagion effects, also known as peer effects or social influence process, have become more and more central to social science, especially with the availability of longitudinal social network data. However, contagion effects are usually difficult to identify, as they are often entangled with other factors, such as homophily in the selection process, the individual’s preference for the same social settings, etc. Methods currently available either do not solve these problems or require strong assumptions. Following Shalizi and Thomas (2011), I frame this difficulty as an omitted variable bias problem, and I propose several alternative estimation methods that have potentials to correctly identify contagion effects when there is an unobserved trait that co-determines the influence and the selection. The Monte-Carlo simulation results suggest that a latent-space adjusted estimator is especially promising. It outperforms other estimators that are traditionally used to deal with the unobserved variables, including a structural equation based estimator and an instrumental variable estimator.     

现代领导增强非权力性影响力刍论

现代领导如何增强领导者的影响力,除正确运用权力性影响力的作用外,努力提高非权力性影响力尤其重要.非权力性影响力主要来源于领导者个人的品德、才能、知识与感情等因素.     

辽代燕云地区佛教文化探论

辽代燕云地区崇佛信教者不分民族(汉、契丹均有)、不分阶层(贵族、平民均有)、不分性别(有男也有女),呈现出普及性和大众化的趋势;广大僧俗信徒组邑社、建寺庙塔幢、刻经讲经,佛事活动呈现多样性和繁复化倾向;佛教流派以密宗为主,并吸纳其他宗派教义“有用”成分及契丹原始萨满教中与密宗教义相类部分,同时杂采西域和中原佛教,文化内涵呈现兼容性和地域化特征。辽代燕云地区佛教文化之所以出现繁盛景象,尽管成因错综复杂,但却有它的客观性和必然性,主要与唐及五代两次灭佛、契丹皇帝支持、社会民众需求及经济利益驱动有关。     

城市老年人社会活动参与对其健康的影响--基于CHARLS 2011年数据

基于2011年“中国健康与养老追踪调查”全国基线调查数据,研究城市老年人社会活动参与对其健康的影响。研究结果发现社会活动参与对老年人日常生活活动能力、抑郁情绪均有显著影响。社会活动参与越多的老年人,在日常生活活动能力方面表现得越好;抑郁情绪也越少。可见,社会活动参与能有效改善老年人的健康水平。本文的研究结论支持了活动理论的观点,即老年人参与社会活动,可以增进他们的身体和心理健康水平。此外,本文还发现性别、年龄、婚姻状况、医疗保险、吸烟、喝酒等变量均对老年人健康有显著影响。     

Gender and social conformity: Do men and women respond differently to social pressure to vote?

In this paper, we re-analyze data from a large-scale field experiment (N = 344,084) on voter turnout in order to determine whether men and women respond differently to social pressure aimed at voter mobilization. To date, there have been mixed results regarding the interaction between a person’s gender and receptivity to social influence. On the whole, our analyses confirm prior findings that social pressure increases voter turnout but uncover little to no evidence of gender differences in receptivity to social pressure cues in the context of political participation.     

Developing an undue influence screening tool for Adult Protective Services

The study purpose was to develop and pilot an undue influence screening tool for California’s Adult Protective Services (APS) personnel based on the definition of undue influence enacted into California law January 1, 2014. Methods included four focus groups with APS providers (n = 33), piloting the preliminary tool by APS personnel (n = 15), and interviews with four elder abuse experts and two APS administrators. Social service literature—including existing undue influence models—was reviewed, as were existing screening and assessment tools. Using the information from these various sources, the California Undue Influence Screening Tool (CUIST) was developed. It can be applied to APS cases and potentially adapted for use by other professionals and for use in other states. Implementation of the tool into APS practice, policy, procedures, and training of personnel will depend on the initiative of APS management. Future work will need to address the reliability and validity of CUIST.     

The expected and unexpected media effects on youth’s (mis)perceptions of peer norms: Chinese college students’ overestimation of peer smoking prevalence

Youth’s perceptions of peer norms have profound effects on their attitudes and behaviors. Unfortunately, their perceptions of peers tend to be biased. To investigate the role of media in the formation of misperceived peer norms, the current study tested and compared two media-effect mechanisms: the direct exemplar mechanism and the indirect influence of presumed influence (IPI) mechanism. The two mechanisms were tested in a sample (n = 1746) that is representative of college students in one large university in China, based on which the actual and perceived campus smoking rates were examined. The individual-level perceived peer smoking prevalence was then analyzed in comparison with the campus-level actual smoking prevalence. The results revealed serious overestimations of peer smoking prevalence. As predicted, pro-smoking media content significantly heightened smoking prevalence estimates through both exemplar and IPI mechanisms. In contrast, anti-smoking messages did not elicit any intended effect through the IPI mechanism, but showed a boomerang effect through the exemplar mechanism. These findings suggest that both pro- and anti-smoking media content may be responsible for inflated perceptions of peer smoking among youth.     

Local influence in seemingly unrelated regression model with ridge estimate

Local influence is a well-known method for identifying the influential observations in a dataset and commonly needed in a statistical analysis. In this paper, we study the local influence on the parameters of interest in the seemingly unrelated regression model with ridge estimation, when there exists collinearity among the explanatory variables. We examine two types of perturbation schemes to identify influential observations: the perturbation of variance and the perturbation of individual explanatory variables. Finally, the efficacy of our proposed method is illustrated by analyzing [13 A. Munnell, Why has productivity declined? Productivity and public investment, New Engl. Econ. Rev. (1990), pp. 3–22. [Google Scholar]] productivity dataset.     

Estimation and diagnostic for skew-normal partially linear models

Partially linear models (PLMs) are an important tool in modelling economic and biometric data and are considered as a flexible generalization of the linear model by including a nonparametric component of some covariate into the linear predictor. Usually, the error component is assumed to follow a normal distribution. However, the theory and application (through simulation or experimentation) often generate a great amount of data sets that are skewed. The objective of this paper is to extend the PLMs allowing the errors to follow a skew-normal distribution [A. Azzalini, A class of distributions which includes the normal ones, Scand. J. Statist. 12 (1985), pp. 171–178], increasing the flexibility of the model. In particular, we develop the expectation-maximization (EM) algorithm for linear regression models and diagnostic analysis via local influence as well as generalized leverage, following [H. Zhu and S. Lee, Local influence for incomplete-data models, J. R. Stat. Soc. Ser. B 63 (2001), pp. 111–126]. A simulation study is also conducted to evaluate the efficiency of the EM algorithm. Finally, a suitable transformation is applied in a data set on ragweed pollen concentration in order to fit PLMs under asymmetric distributions. An illustrative comparison is performed between normal and skew-normal errors.