Variable selection in additive quantile regression using nonconcave penalty

This paper considers variable selection in additive quantile regression based on group smoothly clipped absolute deviation (gSCAD) penalty. Although shrinkage variable selection in additive models with least-squares loss has been well studied, quantile regression is sufficiently different from mean regression to deserve a separate treatment. It is shown that the gSCAD estimator can correctly identify the significant components and at the same time maintain the usual convergence rates in estimation. Simulation studies are used to illustrate our method.     

天津城市风貌塑造中的非物质要素传承

天津建卫六百年以来．社会文化的演变经历了数个重要过程．每个过程对天津城市风貌的塑造都起到了不同的作用。纵观这六百多年的城市建设历史不难发现．天津城市文化及核心价值观体现在如下几方面：     

自然灾害中的社会资本研究

自然灾害具有复杂的社会属性,在近期的灾害研究中,研究者开始引入"社会资本"这一社会结构性资源的概念,分析社会资本在灾害中的角色和作用.本文对相关的理论与经验研究的综述表明,微观层面上的社会资本(个人通过社会网络可获得的资源)可帮助受灾者获取有关灾害的信息,得到救援、物质支持和精神鼓励等实质性资源;而表现为公众自愿组成的公民组织、人际信任以及合作与利他的社会规范的宏观社会资本则可以促使受灾社区及居民的团结合作,更积极地参与到灾后重建工作中来.     

对国有资产中有形资产流失问题的探讨

国有资产中有形资产的流失存在动态流失与静态流失两种形式,动态流失因产权不清、管理不严或产权交易中规则不健全所致,具体又可分为经营性动态流失和人为性动态流失．静态流失与其是否进入市场交易有关．加强经济立法,完善和发展产权交易市场等可减少或避免国有有形资产的流失。     

加入WTO后的南京人力资源开发与管理战略思考

加入ＷＴＯ以后,我们将面临一个更加对外开放的竞争环境,这种新环境将会对南京的人力资源存量和结构产生何种影响,我们将采取何种人力资源的开发和管理战略对策是南京经济保持可持续发展的重要内容之一。 南京的人力资源密集在中国是名列前茅的。国有经济企业和事业单位的专业技术人员有３０多万,其中高级专业技术人员的比重为 １０％以上;在宁高校的正副教授有近７０００余人,在校研究生有万余人［１］。 然而在我们对南京地区高新技术企业的实证分析显示,无论是三资企业、国有企业还是私营企业都认为阻碍企业技术创新的主要制约因…     

The changing landscape of public service delivery systems for disabled people in China: a Shanghai case study

This article will consider the current development of an emerging contract culture for the delivery of social services and its impact on disabled people in China. The discussion is based on an original qualitative study in Shanghai. The past 30 years have seen dramatic changes in China, which in parts have led to improvements in the lives of disabled people. The China Disabled Persons’ Federation (CDPF) became a key player in delivering these changes with the government. However, the CDPF is being criticized by disabled people for being too bureaucratic and not being effective enough in its delivery of services. One of its responses is to work with newly emerging not-for-profit organizations (NPOs) of and for disabled people. The CDPF has now begun to contract the delivery of some services to such NPOs. It is hoped that this may improve their effectiveness but the development of a contract culture in the delivery of services for disabled people may also be seen to pose a threat.     

环境信息不对称、机构投资者实地调研与企业环境治理

基于信息不对称理论,本文以2013-2016年深交所重污染行业上市公司为研究样本,分析了机构投资者实地调研对企业环境治理的影响及其作用机制。研究发现,机构投资者实地调研对企业环境治理具有积极的推动作用;在环境信息披露较差以及本地子公司较多的企业中,机构投资者实地调研的环境治理作用更为明显。进一步考察实地调研对企业环境治理的影响路径发现,机构投资者实地调研推动了企业环境治理的资本市场监督和媒体监督。本文的研究验证了信息不对称理论在环境治理中的作用,拓宽了实地调研经济后果的研究领域,对于深入理解并推动我国企业环境治理具有重要的现实意义。     

要素匹配与中国投资效率空间差异性——基于双层嵌套型函数的分解研究

本文基于四要素双层嵌套的生产函数,利用1990-2016年全国层面及省际层面数据测算投资效率,并分析其空间结构特征及演变轨迹,检验投资效率匹配效应影响因素。研究发现：①1990-2016年我国整体投资效率呈下降趋势,资本-技能劳动匹配效应与整体投资效率走势趋同,快速累积的资本存量和不断升级的资本质量与短缺的技能劳动之间矛盾突出。②东中西部地区投资效率增长非一致性明显。东部地区资本相对投资效率明显高于中西部,但下降幅度大于中西部,中西部与东部地区之间差距缩小,其中匹配效应是区域间投资效率非平衡的主要成因。③若产业结构升级的技能劳动需求不能满足,将引发要素错配,不利于有效投资。房价与工资提升分别通过影响技能劳动供给和需求抑制要素匹配效率;教育和公路设施会对地区要素匹配产生积极影响,改善地区间投资效率非均衡性;地区投资效率存在显著正向空间相关性,毗邻地区的要素流动和经济发展相近地区的技术溢出均对投资效率产生积极的影响。     

Understanding Service Contracting and Its Impact on NGO Development in China

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - The Chinese government and human service NPOs are joining the bandwagon of service contracting with enthusiasm. Although...     

The reproductive health indices and sex hormone levels in middle-aged and elderly Chinese men

Objective: The aim of this study was to analyze the age-related recession trajectory of reproductive health indices in middle-aged and elderly Chinese men.

Methods: A population-based cross-sectional study was conducted in Jiashan County, Zhejiang in 2012. Healthy men between 40 and 80 years of age were considered eligible for the study. Physical examination and the sex hormones were measured. The subjects were assessed based on the 5-item version of the International Index of Erectile Function (IIEF-5) for Erectile Dysfunction (ED), and Aging Males’ Symptoms (AMS) scale for Symptomatic Late-Onset Hypogonadism (SLOH).

Results: TG showed a decrease at age 60 years. Testis volume and TT did not show significant difference among the four age groups; cFT began to decrease at age 50 years and Bio-T decreased faster at age 50 years. SHBG and LH increased faster at age 50 and 70 years, respectively. IIEF5 score decrease faster at age 60 years. AMS scores increased faster at age 70 years. With the increase in age, the symptoms of ED and SLOH became severer.

Conclusion: Different indices on reproductive health of men showed turning points at different ages. At first, androgenic sex hormones decreased faster, and then erectile dysfunction got severer, and the last overall male syndromes declined.