Subsampling-extrapolation bandwidth selection in bivariate kernel density estimation

This paper focuses on bivariate kernel density estimation that bridges the gap between univariate and multivariate applications. We propose a subsampling-extrapolation bandwidth matrix selector that improves the reliability of the conventional cross-validation method. The proposed procedure combines a U-statistic expression of the mean integrated squared error and asymptotic theory, and can be used in both cases of diagonal bandwidth matrix and unconstrained bandwidth matrix. In the subsampling stage, one takes advantage of the reduced variability of estimating the bandwidth matrix at a smaller subsample size m (m < n); in the extrapolation stage, a simple linear extrapolation is used to remove the incurred bias. Simulation studies reveal that the proposed method reduces the variability of the cross-validation method by about 50% and achieves an expected integrated squared error that is up to 30% smaller than that of the benchmark cross-validation. It shows comparable or improved performance compared to other competitors across six distributions in terms of the expected integrated squared error. We prove that the components of the selected bivariate bandwidth matrix have an asymptotic multivariate normal distribution, and also present the relative rate of convergence of the proposed bandwidth selector.     

Tempered Mittag-Leffler Lévy processes

In this article, we introduce tempered Mittag-Leffler Lévy processes (TMLLP). TMLLP is represented as tempered stable subordinator delayed by a gamma process. Its probability density function and Lévy density are obtained in terms of infinite series and Mittag-Leffler function, respectively. Asymptotic forms of the tails and moments are given. A step-by-step procedure of the parameters estimation and simulation of sample paths is given. We also provide main results available for Mittag-Leffler Lévy processes (MLLP) and some extensions which are not available in a collective way in a single article. Our results generalize and complement the results available on Mittag-Leffler distribution and MLLP in several directions. Further, the asymptotic forms of the moments of the first-exit times of the TMLLP are also discussed.     

金融周期、金融波动与中国经济增长——基于省际面板门槛模型的研究

本文应用面板门槛模型,研究了2005-2017年间我国31个省（市、自治区）金融波动对经济增长的影响。研究发现,随着金融周期所处阶段的变化,金融波动对经济增长会产生显著的非对称性双重门槛效应,主要体现为如下两点：首先,金融周期处于膨胀期、平稳期和萧条期时金融波动对经济增长会产生负向影响,但从影响系数值的大小来看,处于膨胀期时最大,是后两者的2倍之多,处于平稳期时最小且并不显著;其次,分区域的稳健性检验表明,金融发展水平高的区域双重门槛值出现得早,且两个门槛值间的区间要比金融发展水平低的区域宽28%。这些结论说明,经济增长对于金融波动的容忍弹性会随着金融周期所处的阶段而变化,金融发展水平的提高会放大经济增长对金融波动的容忍区间,但也会加速金融周期处于膨胀期时爆发金融危机的可能性,这使得当前我国存在着进一步发展金融水平和严控金融风险的矛盾,对此本文也提出了相应的政策建议。     

信任：当代经济社会学研究的新视野

20世纪70年代以来,作为对"经济学帝国主义"入侵的一种回应,信任问题逐渐成为西方经济社会学研究的一个热点。西方经济社会学家,或者在批判新古典经济学的理论和方法的基础上,或者直接借鉴新古典经济学的理论和方法,从社会资本的角度切入,把信任作为一种社会资本的特定形式,通过研究信任与经济秩序、经济交易及其成本、经济效率和效益、经济繁荣和发展之间的关系,来阐明信任这种社会资本在经济生活中的作用。西方经济社会学家对于信任问题的研究及其所取得的成果,不仅为经济社会学在当代的研究和发展开阔了新视野,展示了新空间,而且对于中国社会主义市场经济建设具有重大的现实指导意义。     

投资与中原经济区发展关系研究——基于1989-2009年河南省的时间序列数据分析

投资是中原经济区建设的重要着力点。以河南为例,利用河南省1989-2009年的时间序列数据,通过ADF单位根检验、Granger因果关系检验等,实证分析了投资与经济发展之间的关系。结果表明：投资增长与经济发展之间存在双向的因果关系。     

教育对经济增长贡献算法的改进

本文就教育对经济增长贡献已有的算法及其缺陷进行评述,考虑到AK模型能够比较好地刻画我国的经济增长以及教育本身的延时性,本文提出两条改进意见:发达地区可采用舒尔茨的教育资本存量法,非发达地区和全国范围宜在此基础上选用延期回归方程法,本文还结合深圳1978~1994和中国1978~1996年的样本对此作出解释和验证.     

京津冀人口集聚对能源消费的影响

京津冀作为我国重要的人口集聚区,其区域发展面临严重的能源和环境问题。首先,基于STIRPAT模型构建京津冀面板数据模型,研究1990—2017年京津冀人口密度、经济增长、产业结构和环境规制对能源消费的影响。其次,采用SVAR模型通过脉冲响应函数和方差分解,研究京津冀人口密度变动对能源消费的作用机理和动态影响关系。结果显示,京津冀三地的人口密度、人均实际GDP与能源消费之间存在正向影响关系,其中河北省影响系数最大;北京和天津第三产业占比与能源消费之间存在反向影响关系,河北省第三产业占比对能源消费的影响不显著;北京和天津的环境规制对能源消费影响不显著,河北省环境规制对能源消费具有正向影响;京津冀地区和京冀两地人口密度变动对能源消费的影响在短期呈现负向效应,但是在中长期京津冀地区和三地人口密度变动对能源消费的影响均先上升然后缓慢下降,人口集聚具有集约用能效应。相对于能源消费自身影响而言,京津冀人口密度变动对能源消费的贡献相对较小,其影响效应有限。最后,对京津冀人口流动和能源消费一体化协同发展提出对策建议。     

理工院校金融专业实验室和实习基地建设的几点建议

理工院校金融专业的起步比一些专业性和综合性院校晚,其实验室和实习基地建设明显存在不足。为此,理工院校必须通过制定科学合理的规划,充分加强与领导以及外界企业的联系,学习和借鉴先进的经验、将"产、学、研"完美结合,这样才能实现良好的社会和经济效益。     

伊斯兰经典经济思想特点概论

以（《古兰经》和圣训为基础的伊斯兰教法与东西方传统的经济思想体系所根基的历史文化土壤不同,前者必然体现出许多独特之处。从宗教与世俗的不同视角来看,伊斯兰经典经济思想也具有与世俗经济思想的不同之处。伊斯兰经典经济思想具有浓厚的宗教神学色彩、深刻的道德烙印与浓厚的福利精神、义利统一和相对均平的观念特点、非逻辑理性色彩和法律化、制度化、生活方式化的特点。伊斯兰教经典经济思想的内涵深邃,外延十分丰富。     

India’s Social Development in a Decade of Reforms: 1990–91/1999–2000

The economic reforms initiated in India in 1991 have brought about visible upliftment of economic conditions of the country. This paper examines if the economic process is associated with an enhancement of India’s social development in equal measure in the reform decade of nineties. Ray (1989) considered thirteen social indicators of India and constructed the country’s social development index (SDI) as a certain weighted average of the selected indicators, for the years between 1950–51 and 1975–76. The present work broadly follows Ray (1989) in tracking the social development in the decade of economic reforms from 1990–91 to 1999–2000. The movement of SDI in nineties has been compared with the movements of India’s per capita income and plan expenditure on the social sector. The results show that though there has been growth in the social sector, it is not by far quite encouraging and perhaps more needs to be done in the social sector. The views expressed in the article are those of the author and not of the institution he serves.