Smoothed empirical likelihood analysis of partially linear quantile regression models with missing response variables

In this paper, we consider the estimation and inference of the parameters and the nonparametric part in partially linear quantile regression models with responses that are missing at random. First, we extend the normal approximation (NA)-based methods of Sun (2005) to the missing data case. However, the asymptotic covariance matrices of NA-based methods are difficult to estimate, which complicates inference. To overcome this problem, alternatively, we propose the smoothed empirical likelihood (SEL)-based methods. We define SEL statistics for the parameters and the nonparametric part and demonstrate that the limiting distributions of the statistics are Chi-squared distributions. Accordingly, confidence regions can be obtained without the estimation of the asymptotic covariance matrices. Monte Carlo simulations are conducted to evaluate the performance of the proposed method. Finally, the NA- and SEL-based methods are applied to real data.     

运用柯布-道格拉斯生产函数模型分析研发活动的成效

本文采用柯布-道格拉斯生产函数模型,基于1995-2008年研发资金的投入和产出相关数据,对我国研发活动的成效进行了分析。总体而言,我国应该加大研发经费的支出。但如果我们更注重研发成果的质量,则研发资金的分配应该倾向于加大支持的强度;如果我们更注重研发成果的数量,则研发资金的分配应该倾向于支持更多的研发人员从事研发活动。同时,从长期来看,无论是以研发活动的质量还是数量为衡量标准,都应该增加对研发活动的投入,以实现研发活动的最佳规模。     

Infinite horizon reflected backward stochastic differential equations with Markov chains

We first give the existence and uniqueness results for infinite horizon backward stochastic differential equations with Markov chains, taking advantage of the martingale representation theorem and fixed point principle. Then we prove the well-posedness results for infinite horizon reflected backward stochastic differential equations with Markov chains, by virtue of the Snell envelope theory and contraction mapping method. Comparison theorems for the above two kinds of equations are also obtained, via the linearization approach or properties of reflected backward stochastic differential equations, respectively.     

从创新教育要求谈高等学校实验室的建设

随着教育改革和创新教育的发展进程,高等学校应以什么样的思路建设实验室,使之真正成为培养大学生创新能力,提高大学生综合素质的重要基地,是一个值得深刻思考与探索的问题。     

基于BCA模型的中国经济波动因素的再测算

文章以动态随机一般均衡模型作为基本分析框架,构建一个带有时变摩擦的实际经济周期(RBC)模型.在考虑经济结构变化的前提下,使用经济周期测度(BCA)模型对1978-2015年我国宏观经济波动特征进行研究和引起波动的因素进行分解,实证结果表明:1993年是我国经济系统结构变化的断点,1978-1992年我国经济波动主要受技术冲击影响,其他的冲击因素具有缓解经济波动的作用;1993-2015年,我国经济波动主要受投资冲击的影响,而技术冲击、劳动冲击和外部冲击也起到部分影响;改革开放以来,我国经济波动源由从单一波动源向多种冲击共同作用的趋势发展.     

考虑决策者风险偏好的区间粗糙数多属性决策方法

文章针对属性值为区间粗糙数的多属性决策中如何考虑决策者风险偏好问题进行了研究,提出了一种新的区间粗糙数多属性决策方法.首先基于属性值与正负理想点距离远近来反映决策者偏好的思想定义了偏好距离,在此基础上利用熵权法计算属性权重,然后计算各方期望效用并按此排序.最后通过算例证明了此方法有效.     

On list <Emphasis Type="Italic">r</Emphasis>-hued coloring of planar graphs

A list assignment of G is a function L that assigns to each vertex \(v\in V(G)\) a list L(v) of available colors. Let r be a positive integer. For a given list assignment L of G, an (L, r)-coloring of G is a proper coloring \(\phi \) such that for any vertex v with degree d(v), \(\phi (v)\in L(v)\) and v is adjacent to at least \( min\{d(v),r\}\) different colors. The list r-hued chromatic number of G, \(\chi _{L,r}(G)\), is the least integer k such that for every list assignment L with \(|L(v)|=k\), \(v\in V(G)\), G has an (L, r)-coloring. We show that if \(r\ge 32\) and G is a planar graph without 4-cycles, then \(\chi _{L,r}(G)\le r+8\). This result implies that for a planar graph with maximum degree \(\varDelta \ge 26\) and without 4-cycles, Wagner’s conjecture in [Graphs with given diameter and coloring problem, Technical Report, University of Dortmund, Germany, 1977] holds.     

Gini index estimation for lifetime data

Lifetime data is often right-censored. Recent literature on the Gini index estimation with censored data focuses on independent censoring. However, the censoring mechanism is likely to be dependent censoring in practice. This paper proposes two estimators of the Gini index under independent censoring and covariate-dependent censoring, respectively. The proposed estimators are consistent and asymptotically normal. We also evaluate the performance of our estimators in finite samples through Monte Carlo simulations. Finally, the proposed methods are applied to real data.     

天津东疆保税港区发展自由贸易区可行性及政策建议

2006年国务院批准天津滨海新区为国家综合配套改革试验区,提出借鉴国际通行做法,设立天津东疆保税港区。天津东疆保税港区是继上海洋山之后,国家批准设立的第二个保税港区,是我国目前面积最大的保税港区。国家赋予天津东疆保税港区先行先试的权力,