人口计生基本公共服务均等化研究

人口计生基本公共服务不同于其他公共服务,旨在满足个人和家庭实行节育的特殊需求。公共服务均等化属于公共财政的范畴,无论是制定基本公共服务标准,还是确立基本公共服务内容,都无法绕过财政能力的区域差异问题。借鉴标准人系数法定量测算人口计生基本公共服务均等化资金需求,试图构建均等化分配模型,为推进区域人口计生基本公共服务均等化提供可靠依据。     

A method for constructing asymmetric pair-copula and its application

Pair-copula has become a hot spot in the research of both theory and application of statistics. Therefore, proper construction of pair-copula is an area worthy of study. Considering the asymmetry of variate dependence in practical applications and the disadvantages of the widely used asymmetric copulas, we propose a method to construct asymmetric pair-copula. In our method, we treat the asymmetric bivariate copula constructed by Liebscher's method as a generator, using this generator to construct asymmetric pair-copula. Also, on the basis of our method, we propose and prove a reference for selecting copula family in the construction. To verify the method, we construct asymmetric copulas and asymmetric pair-copulas using the daily runoff data collected at Yichang hydrological station to describe the extreme drought events of Yangtze River. After comparing the models in some aspects, we accept a model we construct, and the result displays the feasibility and practicality of the method we propose.     

Robust adaptive model selection and estimation for partial linear varying coefficient models in rank regression

Partial linear varying coefficient models are often used in real data analysis for a good balance between flexibility and parsimony. In this paper, we propose a robust adaptive model selection method based on the rank regression, which can do simultaneous coefficient estimation and three types of selections, i.e., varying and constant effects selection, relevant variable selection. The new method has superiority in robustness and efficiency by inheriting the advantage of the rank regression approach. Furthermore, consistency in the three types of selections and oracle property in estimation are established as well. Simulation studies also confirm our method.     

“一带一路”背景下中国与美国金融生产性服务业产业关联问题研究

为了比较研究中美两国金融服务业的发展差异,理清中国在加入世界贸易组织（WTO）后金融服务业的演进趋势,探究中国金融服务业与其他国民产业部门的关联关系,通过对比分析中美两国金融服务业的中间投入率以及产业关联系数,在当前中国处于新常态下的经济结构转型时期下,尝试从比较结果中得出如何深层次地深化金融改革、如何进一步研究金融生产性服务业与实体经济关联关系并探索其如何更好地服务于实体经济的经验。鉴于金融业的发展对于促进和稳定国民经济发展的作用,采用WIOD数据库中中美两国2007～2014年的9个行业部门投入产出数据,对两国金融服务业以及整体服务业的中间投入率、产业关联系数进行横向和纵向的比较研究。研究表明:中国金融服务业近年来发展迅速,但是我国服务业的整体发展水平还不及美国;美国金融生产性服务业的产业关联系数均大于中国,反映了中国金融生产性服务业与世界发达国家的差距和不足。随着“一带一路”的深入实施,中国应推进深层次金融改革、加大服务业投入占比等,以让金融业更好服务实体经济。     

基于城市复合生态系统理论的城市生态交通发展评价

针对当前中国城市化进程中城市交通存在的各种外部性问题,基于城市复合生态系统理论,构建了综合评价城市生态交通发展水平的指标体系,综合运用层次分析法和数据包络分析法构建评价模型,以此模型为基础,第一次提出了生态交通指数的计算方法,最后从区域协同发展视角出发,创新性地利用Theil系数对区域内城市生态交通发展水平的空间差异进行解构。为验证该模型的可行性及其对现实政策规划的指导作用,运用该模型对2006~2015年京津冀区域内5个城市的生态交通发展水平进行了评价研究。实证结果表明,该模型可行性良好,实证结果能够客观反映各个城市生态交通发展状况及存在问题,有利于指导现实政策规划;近10年来京津冀区域内部发展差异逐渐缩小,但整体发展水平仍然较慢,因此科学系统且具体可实施的规划方案是加快推动京津冀交通一体化的重要举措;区域内部城市生态交通发展水平随经济发展整体上呈现出“倒U型”发展趋势,亟待探究北京、天津等大城市生态交通指数的上升拐点;该区域平均生态交通指数呈现出下降趋势的主要原因在于机动车的过快增长,因而需要在短期内控制机动车的增长速度与排放水平,提高公共交通基础设施的投资建设水平并发展低碳交通方式则是长期内需要重点关注的问题。     

Measuring association between nominal categorical variables: an alternative to the Goodman–Kruskal lambda

As a measure of association between two nominal categorical variables, the lambda coefficient or Goodman–Kruskal's lambda has become a most popular measure. Its popularity is primarily due to its simple and meaningful definition and interpretation in terms of the proportional reduction in error when predicting a random observation's category for one variable given (versus not knowing) its category for the other variable. It is an asymmetric measure, although a symmetric version is available. The lambda coefficient does, however, have a widely recognized limitation: it can equal zero even when there is no independence between the variables and when all other measures take on positive values. In order to mitigate this problem, an alternative lambda coefficient is introduced in this paper as a slight modification of the Goodman–Kruskal lambda. The properties of the new measure are discussed and a symmetric form is introduced. A statistical inference procedure is developed and a numerical example is provided.     

On some aspects of a flexible class of additive Weibull distribution

Here we consider a more flexible class of the additive Weibull distribution of Xie and Lai (Reliab. Eng. Syst. Safety, 1995) and investigate some of its important properties such as expressions for its cumulative distribution function, reliability measures, quantile function, characteristic function, raw moments, incomplete moments, etc. The distribution and moments of order statistics are obtained along with certain structural properties. The maximum-likelihood estimation of the parameters of the distribution is attempted and the usefulness of the model in certain applied areas is illustrated with the help of certain real life data sets.     

Wavelet estimation in time-varying coefficient time series models with measurement errors

The article studies a time-varying coefficient time series model in which some of the covariates are measured with additive errors. In order to overcome the bias of estimator of the coefficient functions when measurement errors are ignored, we propose a modified least squares estimator based on wavelet procedures. The advantage of the wavelet method is to avoid the restrictive smoothness requirement for varying-coefficient functions of the traditional smoothing approaches, such as kernel and local polynomial methods. The asymptotic properties of the proposed wavelet estimators are established under the α-mixing conditions and without specifying the error distribution. These results can be used to make asymptotically valid statistical inference.     

简议二阶变系数线性微分方程解法

在理工科专业中,许多力学问题可归结为二阶微分方程,其中如何求首积分以及特解是十分重要的。许多教材对可降阶二阶微分方程,常系数线性微分方程,拉普拉斯交换解微分方程都作了比较详细的介绍,但对于二阶交系数线性微分方程的解法,没有一个定论。本文就这一问题进行探讨。