Covariance structure approximation via gLasso in high-dimensional supervised classification

Recent work has shown that the Lasso-based regularization is very useful for estimating the high-dimensional inverse covariance matrix. A particularly useful scheme is based on penalizing the ?₁ norm of the off-diagonal elements to encourage sparsity. We embed this type of regularization into high-dimensional classification. A two-stage estimation procedure is proposed which first recovers structural zeros of the inverse covariance matrix and then enforces block sparsity by moving non-zeros closer to the main diagonal. We show that the block-diagonal approximation of the inverse covariance matrix leads to an additive classifier, and demonstrate that accounting for the structure can yield better performance accuracy. Effect of the block size on classification is explored, and a class of asymptotically equivalent structure approximations in a high-dimensional setting is specified. We suggest a variable selection at the block level and investigate properties of this procedure in growing dimension asymptotics. We present a consistency result on the feature selection procedure, establish asymptotic lower an upper bounds for the fraction of separative blocks and specify constraints under which the reliable classification with block-wise feature selection can be performed. The relevance and benefits of the proposed approach are illustrated on both simulated and real data.     

Health-Related Quality of Life Among Abused Women One Year After Leaving a Violent Partner

This is the first follow up study measuring quality of life among abused women who have left their abusive partner. The women (n = 22) answered a questionnaire while staying at women’s shelter and one year later. The aim was to examine long-term effects of intimate partner violence against women on health-related quality of life. Health-related quality of life was measured using the SF-36 Health Survey and the WHOQOL-BREF. The meantime for living in a violent partnership was 11 years, most of the women had children under 10 years living with them, low income and were on sickness absence or disability pension. About half of the women had experienced threats of violence and 6 had experienced violent acts after leaving their partner. SF-36 scores after one year were significantly better in vitality (t-test, P < 0.001), mental health (t-test P < 0.001) and social domains (t-test, P < 0.04). WHOQOL-BREF scores did not change significantly from baseline, showing that the SF-36 showed more responsiveness in this population. Regression analysis showed that serious physical violence reported at baseline predicted significantly less improvement in physical and mental health and role-emotional in the SF-36 and in social relationships and environmental health in the WHOQOL-BREF. High psychological violence at baseline predicted significantly less improvement in mental health in the SF-36 and in social relationships and environmental health in the WHOQOL-BREF.     

股权性质 、两权分离与企业过度投资行为

以我国2004-2009年沪深两市上市公司为样本,参照Vogt投资研究模型,对我国上市公司的资本投资行为进行研究,结果表明：我国上市公司普遍存在过度投资行为,而且相比非国有控制的上市公司,国有控股的上市公司过度投资更为严重;现金流权比例的增加和两权分离程度的降低能够对企业过度投资产生抑制作用,且相比非国有控股公司,这种抑制作用在国有控股的上市公司中表现更为明显。     

试论我国的商事立法模式

本文通过对我国民商分立与民商合一立法模式的论争评述,以及当前民商立法现状的检讨,指出我国的商事立法应选择坚持民商实质合一理念下,制定<商事通则>的立法形式适当分立的模式.     

家庭自治、国家干预与夫妻分居的法律规制

分居制度在婚姻法中有举足轻重的地位,其合理性在于使夫妻人身自由的实现与家庭合伙功能的兼顾,但我国的有关立法与实践中的现实却是在分居过程中过于强调家庭自治。通过比较其他国家立法中该项制度在结构和功能上的异同及发展趋势,可以发现,现代家庭法领域已经深刻地发生了家庭自治与适当的国家干预相互协调的现象。因此,我国立法应该将夫妻分居纳入法律行为制度的调整之下,以完善分居中的自治与法治。     

市民社会与社会主义民主政治建设

市民社会是民主政治的摇蓝,它孕育着民主所需要的一切.在社会管理民主化、国家政治文明化的发展进程中,市民社会是不可或缺的强力支撑.在新全球化时代,中国社会主义政治文明的建设同样离不开市民社会民主功能的有效发挥,这既有其理论依据又有其现实条件.构建新市民社会,将给中国政治转型开辟出一条新的路径,使政治民主化由上而下的推进转为上下的双向建构和良性互动,并将塑造起健康完满的政治人格,高扬公民的政治主体性,创建丰富的社会资本,化解初露的合法性危机.     

公立高校两权分离的现实基础与动力机制分析

市场经济体制下,利用市场机制配置资源及政事分离是我国公立高校面临的迫切要求。而这一要求得以付诸实践的前提之一就是实行高校所有权和经营权的分离。文章认为,当前我国公立高校两权分离是不彻底的,并指出高校的所有权和经营权存在分离的现实基础以及高校与市场、高校与政府间矛盾生成的动力机制,这些决定了两权分离将成为高校未来发展的合理方向。     

甾体皂苷提取分离及结构研究方法

甾体皂苷是一类重要的生物活性物质,是许多药用植物的有效成分之一,随着人们对甾体皂苷生理活性的研究,如何从天然产物中提取分离甾体皂苷及其结构研究引起人们的广泛关注。本文就甾体皂苷的提取分离及结构研究方法作一综述,为进一步开发利用甾体皂苷药用植物资源提供参考。     

夫妻分居后的共同债务认定问题实证研究

对于夫妻分居期间一方所借债务能否认定为共同债务问题,婚姻法第四十一条、司法解释（二）第二十四条确立了“共同生活”和“婚姻关系存续期间”的不同标准.对司法实践中法官的标准适用、举证责任等处理方式分析表明,大多数法官采用共同生活这一实质标准.在夫妻双方分居时,夫妻一方的债务原则上应当推定为一方的个人债务,除非第三人能证明有合理理由信赖这一债务属于一般家事代理范围,或者举债人配偶不能举证债务利益并未用于共同生活.     

我国民事再审程序存在的缺陷及其重构

我国现行民事再审程序的运行并未达到法律救济预期的法律和社会效果,究其原因,既有立法上的缺陷,又有司法实践中的执法不严。对策是:取消人民法院依职权自行决定再审权、限制人民检察院的民事再审抗诉权、建立再审之诉,并重构再审理由、再审管辖。