New recursive estimators of the time-average variance constant

Estimation of the time-average variance constant (TAVC) of a stationary process plays a fundamental role in statistical inference for the mean of a stochastic process. Wu (2009) proposed an efficient algorithm to recursively compute the TAVC with \(O(1)\) memory and computational complexity. In this paper, we propose two new recursive TAVC estimators that can compute TAVC estimate with \(O(1)\) computational complexity. One of them is uniformly better than Wu’s estimator in terms of asymptotic mean squared error (MSE) at a cost of slightly higher memory complexity. The other preserves the \(O(1)\) memory complexity and is better then Wu’s estimator in most situations. Moreover, the first estimator is nearly optimal in the sense that its asymptotic MSE is \(2^{10/3}3^{-2} \fallingdotseq 1.12\) times that of the optimal off-line TAVC estimator.     

论环渤海陆地规划与海洋规划需同时

2006年12月,胡锦涛总书记在中央经济工作会议上提出:"在做好陆地规划的同时,要加强海洋意识,做好海洋规划,完善体制机制,加强各项工作,从政策和资金上扶持海洋经济的发展."     

考古学与未来:工业文明的忧虑

在从考古学角度对玛雅、复活节岛和良渚文明崩溃回顾的基础上,文章从"报酬递减"和"最省力"原理介绍了古代文明崩溃的机制,然后对现代工业文明的发展趋势表示了忧虑.文章认为,今天的地球只不过是一个放大了的玛雅低地和复活节岛.历史教训告诉我们,环境恶化总是文明崩溃的一个前提.面对当代工业文明所面临的人口激增、环境恶化和资源枯竭的严峻形势,我们应该提倡"知足最好"而非"越多越好",避免重蹈古代文明崩溃的覆辙.     

On Bartlett correction of empirical likelihood for regularly spaced spatial data

Bartlett correction constitutes one of the attractive features of empirical likelihood because it enables the construction of confidence regions for parameters with improved coverage probabilities. We study the Bartlett correction of spatial frequency domain empirical likelihood (SFDEL) based on general spectral estimating functions for regularly spaced spatial data. This general formulation can be applied to testing and estimation problems in spatial analysis, for example testing covariance isotropy, testing covariance separability as well as estimating the parameters of spatial covariance models. We show that the SFDEL is Bartlett correctable. In particular, the improvement in coverage accuracies of the Bartlett‐corrected confidence regions depends on the underlying spatial structures. The Canadian Journal of Statistics 47: 455–472; 2019 © 2019 Statistical Society of Canada     

基于“翻转课堂”的大学生信息素质教育设计研究

翻转课堂是一种以学生学习为中心的新型教学方法,通过"翻转课堂"和"传统课堂"的优势比较可知,大学生信息素质教育非常适合这一教学方法,并对"翻转课堂"进行了以学生为中心,以活动为导向的教学设计。     

The Association of Alternative Financial Services Usage and Financial Access: Evidence from the National Financial Capability Study

This study examined the association of financial access and alternative financial services (AFS) using a nationally representative sample from the 2012 National Financial Capability Study (N = 25,509). Structural equation modeling was used to examine the relationship between financial access and AFS usage. Ordinary least squares regression was used to estimate the relationship between banked status and the overall AFS usage as a latent variable while controlling for sociodemographic variables, financial education, financial knowledge, and home ownership. Results suggested that being unbanked was positively associated with AFS usage after controlling for other covariates. Financial education and knowledge, age, gender, marital status, education, household income, and homeownership were significantly associated with AFS usage. These findings have implications for public policy and programs that work with the unbanked.     

广州市农村留守儿童问题研究

基于问卷调查研究广州市农村留守儿童问题。调查显示,广州存在农村留守儿童及其问题,但是,广州农村留守儿童问题程度相对较轻。根本原因是广州作为改革开放的前沿阵地,城乡经济社会发展和二元结构改革取得了重大进展。对广州农村留守儿童问题不能听之任之,要加强农村留守儿童的家庭监护主体责任和学校关爱保护工作。     

论档案价值与档案价值实现

依据档案价值的特性及档案价值实现的规律,对档案价值与档案价值的实现进行了思考。人们只有对档案价值的客观性、潜在性、多元性及其具体表现形式有了深刻的了解,才能切实做好档案利用工作,最大限度地开发和利用档案资源,充分发挥档案的价值。     

社会参与对中老年消费的影响及作用机制研究

本文基于中国健康与养老追踪调查（CHARLS）2018年数据,利用工具变量法及倾向得分匹配方法实证分析社会参与和中老年消费之间的关系,并采用中介效应模型研究社会参与影响中老年消费的作用机制。研究发现：社会参与对中老年总消费、日常性消费、发展性消费、享受性消费均有正向影响,其中对享受性消费的促进作用最为明显。社会参与能通过影响认知能力、投资与缓解信贷约束间接影响中老年消费,且三者的作用机制存在差异;社会参与对中等收入群体、城市消费群体、中年消费群体的影响更大。因此,未来应创造相应条件鼓励中老年人积极进行社会参与,加大对中老年人学习信息技术、参与老年教育的引导和支持力度。同时,加速适老化社交型产品和服务的开发,以有效发挥社会参与对中老年消费的拉动作用。     

关于中国人口控制问题的商榷

中国人口占世界人口1/5,是世界人口最多的发展中国家。中国政府把计划生育政策定为基本国策,并取得了举世瞩目的成就。中国人口基数过大,人均耕地远小于国土面积与中国相当的美国,加上其他不利因素,经有关专家组研究,中国最大环境人口容量为16亿。又经预测,按现行中国人口政策,到2030年前后中国人口将达到16亿。中国人口控制喜忧参半,仍十分严峻,且任重而道远。因此,讨论了中国人口控制的成就和问题,并提出了若干建议供参考。