Generalized Leverage and its Applications

The generalized leverage of an estimator is defined in regression models as a measure of the importance of individual observations. We derive a simple but powerful result, developing an explicit expression for leverage in a general M -estimation problem, of which the maximum likelihood problems are special cases. A variety of applications are considered, most notably to the exponential family non-linear models. The relationship between leverage and local influence is also discussed. Numerical examples are given to illustrate our results     

基于生态学的通讯设备制造业的技术创新种群演化分析

技术创新群是指行业内技术创新主体的集合.分析技术创新种群行为主要是研究行业内技术创新种群量的变化规律,以及行业内不同技术创新种群之间的演化关系.本文应用生态学的种群理论与分析方法,探讨了研究这一问题的方法,并进行了实例验证.     

我国绿色基础设施的经济价值预算与分析

绿色基础设施是自然的生态基础设施和半自然的市政绿色空间的结合,它遵循自然发展的规律,在改善生态环境和保护生物多样性的同时,也蕴藏着新的经济增长点.本研究尝试构建绿色基础设施经济价值评价指标,测算全国各省的绿色基础设施经济价值(2004-2015),探究其区域分布状况,并进一步运用灰色模型预测2016年、2020年和2025年我国绿色基础设施的经济价值,以期提升人们对绿色基础设施的认识,为在城市规划中建设和完善绿色基础设施提供参考,促进生态环境与经济的良性循环,推动城市可持续发展.     

就近半城市化与去城市两级分化

农民以家庭为单位普遍选择的就近半城市化路径中,人口迁徙具有可逆性：一是从城市回流到农村的可逆性,二是从大城市回流到中小城市的可逆性。这两种可逆性勾勒着我国城市化进程中的“去城市两极分化”机制：类贫民窟作为物理载体仍然会在城市化的过程中存在,但在可逆过程中,它并不会形成一个刚性的城市社会贫民阶层,进而这种可逆性成为城市社会两极分化结构中的弹性要素;特大城市也会产生,但在可逆的过程中,作为纯资源接受者的中小城市将获得人口集聚和经济发展的契机,从而这种可逆性也构成了城市体系两极分化结构中的弹性要素。     

易地扶贫搬迁安置社区的紧张与化解

易地扶贫搬迁安置社区的制度设计,是一种用城市生活取代传统乡土社会生活的逻辑。落实在社区治理实践之中,则常见到形式各异的紧张,主要表现为移民的日常生活与制度之间产生的对立与冲突。以“制度与生活”分析框架解释,能够发现易地扶贫搬迁安置社区治理紧张的原因、表现及正式制度推行的路径依赖。化解易地扶贫搬迁安置社区的治理紧张,一方面正式制度要以开放和包容的态度正视移民搬迁群体的正常诉求,及时进行自我变革;另一方面易地扶贫搬迁社区群众要主动接受制度的规约,尽快实现由传统生活向现代生活的转变。     

中国单身女性的困境: 多元交叉的社会压力和歧视

随着中国单身人口比例的上升,单身人群特别是单身女性群体受到了社会各个层面的关注。目前国内对单身女性的研究主要通过深度访谈来探讨单身未婚女性的身心和生活状态,缺乏系统的理论观照,且访谈样本又大都局限于大城市的中产阶层单身未婚女性,因而限制了研究成果的代表性。从交叉性理论出发,分析中国单身女性面临的宏观(儒家文化和人口调控压力)、中观(媒体的形象控制和代际压力)和微观(性别歧视、年龄歧视和单身歧视)的多元交叉压力和歧视,厘清目前单身女性所受到的压力和歧视,从不同阶层单身女性的需求出发,才能为她们提供切实有效的帮助,并有助于解决目前我国单身人口比例上升的问题,缓解人口老龄化的压力。     

Prediction intervals for future Weibull residual data

In reliability theory, risk analysis, renewal processes and actuarial studies, the residual lifetimes data play an important essential role in studying the conditional tail of the lifetime data. In this paper, based on some observed ordered residual Weibull data, we introduce different prediction methods for obtaining prediction intervals (PIs) of future residual lifetimes including likelihood, Wald, moments, parametric bootstrap, and highest conditional methods. Monte Carlo simulations are performed to compare the performances of the so obtained PIs and one data analysis is performed for illustration purposes.     

Survival in the U.S. petroleum refining industry

Of the 324 petroleum refineries operating in the U.S. in 1982, only 149 were still in the hands of their original owners in 2007. Using duration analysis, this paper explores why refineries change ownership or shut down. Plants are more likely to ‘survive’ with their original owners if they are older or larger, but less likely if the owner is a major integrated firm, or the refinery is a more technologically complex one. This latter result differs from existing research on the issue. This paper also presents a split population model to relax the general assumption of the duration model that all refiners will eventually close down; the empirical results show that the split population model converges on a standard hazard model; the log-logistic version fits best. Finally, a multinomial logit model is estimated to analyze the factors that influence the refinery plant's choices of staying open, closing, or changing ownership. Plant size, age and technology usage have positive impacts on the likelihood that a refinery will stay open, or change ownership (rather than close down).     

Thank God you're here: the coming generation and their role in future‐proofing Australia from the challenges of population ageing

Like much of the industrialised world, Australia's population is ageing, the implications of which are twofold: increasing demand for publicly funded services and a decline in the supply of prime working‐age people. In grappling with the challenges of a diminishing workforce, the Australian Government is currently relying on its migration programs to provide both the much‐needed labour and skills for the resource boom and also to stimulate the economy through population growth. However, there may be another, not yet fully considered solution to the upcoming demographic problem. This paper investigates how the grandchildren of the baby boomers, termed here the Thank God You're Here generation (Gen TGYH), might impact on Australia's predicted workforce shortage. This generation of workers will enter the labour force as the last of the baby boomers reach retirement age, and will not only be bigger in size than preceding generations (Y, X and Baby Boomers), but also potentially be better educated than the retiring generation. This paper will also canvas the opportunities for both Gen TGYH and employers as well as the challenges for policymakers and governments in maximising the opportunity provided by this generation in the Australian economy.