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.     

长途乘客出行行为分析——以天津为例

随着城市社会经济的快速发展,公路主枢纽规划所面临的形势发生了重要变化,规划的理念也需要更新,因此许多主枢纽城市已经完成或正在进行公路主枢纽规划修编工作.     

新教学模式在非金属专业教学中的设计与应用

本文以多媒体网络教学为研究对象,初步探讨多媒体网络技术辅助教学的基本模式,并据此设计了基于多媒体和互联网技术的非金属专业教学系统,使远程异地教学、在线测试等成为可能,优化了传统教学过程,促进了教学质量,为我们提供一个全新的教学模式。     

西方后现代主义音乐思潮的解析

后现代主义作为当下最为前卫的文化思潮,它对包括音乐、文学等众多艺术形式以及哲学观念都有着极为重要的影响。文章以音乐艺术为对象,从对后现代主义的概念和特征的梳理中来探讨当今音乐创作观念及审美等方面表现出的种种后现代主义特征。     

索赔次数的开放式混合泊松分布研究

本文建立了索赔次数的多风险类别混合泊松模型。首先,考虑索赔次数的零膨胀、厚尾性和异质性等特征,建立风险类别待定的开放式混合泊松模型,开放式结构使该模型对实际数据的多样特征和风险类别具有良好的自适应性;其次,定义混合权重参数的iSCAD惩罚函数,实现对权重参数的筛选;最后,借助EM算法求得模型参数,实现对各风险类别下索赔次数的估计。借助iSCAD惩罚函数,给出最优混合数,避免传统混合模型中主观选择的弊端,克服传统混合模型中结构复杂、参数估计没有显式表达式、估计结果不便于解释等问题。基于三组风险特征多样数据的实证分析,本文发现该模型可以显著改进现有模型的拟合效果。     

Expediting youth's entry into employment whilst overlooking precariousness: Flexi‐employability and disciplinary activation in Hong Kong

With an emphasis placed on supply‐side interventions such as skills training and incentives enhancement, active labor market polices (ALMPs) are strongly promoted by international organizations and widely adopted across different welfare regimes to boost employment rates. This article first presents the under‐examined relationship between ALMPs and employment precariousness, which has posed a challenge to the neoliberal notion of employability and activation. Youth‐focused employment policies tend to speed up employment entry whilst downplaying the risk of precariousness and the importance of job quality, and thus further reinforcing the belief that engaging in precarious employment is tolerable if not inevitable. The article then examines the case of Hong Kong, which illustrates that its relatively low rate of youth unemployment may conceal the unfavorable employment conditions confronted by youth. It is argued that the service‐led employment policies and short‐term vocational training define the employability of young workers in terms of labor flexibilities. The coined phase of “flexi‐employability” is characterized by promoting youth's readiness for, and adaptability to, the volatilities and changing demands of the labor market. Arguably, the disciplinary approach to youth activation would only strengthen the work‐first principle by enforcing young people to take up jobs available and leave welfare as soon as possible, but without thoroughly addressing the risks and insecurities generated by the labor market in undermining their well‐being.     

以合意为基础的物权变动立法模式——兼谈我国《物权法》之相关条文

正确理解物权变动立法模式有助于科学合理地构建我国物权法制度;正确认识和理解物权变动的概念、物权变动的原因、合理地评价物权行为理论是正确解读物权变动立法模式的必要理论前提;对大陆法系国家三种典型的物权变动立法模式之正确理解是正确理解物权变动立法模式的必要立法认识;对大陆法系国家三种典型物权变动立法模式的科学合理的评析是正确解读物权变动立法模式的关键。     

普通高校体育选项课之分层教学与目标教学的有机整合

根据普通高校体育选项课教学大纲的要求,对分层教学组织形式和目标教学法进行了系统研究,认为二者的有机整合可以有效提高普通高校体育教学的效果。分层教学与目标教学有机整合是分层制订分别适合不同高校大学生的教学目标和考核目标,因材施教,因需指导,因层评价和动态组合等,是帮助学生提高体育学习效果的较好方法,能够让学生最大限度地发挥自身潜力,从而促进大学生身心健康的发展,并帮助他们养成终身体育意识和体育习惯。     

数学在经济学研究中的角色: 基于金融危机视角的思考

目前学术界在处理经济学和数学之间的关系方面存在一些偏向,必须辩证地看待经济学与数学之间的关系.经济学研究需要数学的帮助,运用数学推理解决经济学问题具有文字逻辑无法比拟的一些优点.不过,数学只是体现和执行经济思想、帮助理解和分析的工具,而非目的,不加限制地将经济学"数学化"会损害经济思想.因此,对数学工具的运用要从经济思想表达的需要出发,服务于经济学研究,而不能代替经济学.