Construction of incomplete Sudoku square and partially balanced incomplete block designs

Abstract

The present article deals with the study of association among the elements of a Sudoku square. In this direction, we have defined an association scheme and constructed incomplete Sudoku square designs which are capable of studying four explanatory variables and also happen to be the designs for two-way elimination of heterogeneity. Some series of Partially Balanced Incomplete Block (PBIB) designs have also been obtained.     

可行能力与农民工的福利状况评价

基于辽宁省沈阳市农民工调查数据,应用森的可行能力理论和模糊数学方法对农民工的福利状况进行整体评价。结果发现,农民工福利水平的总模糊指数为0.365,处于较低水平。分指标看,健康状况方面的福利状况处于较高水平,居住环境和精神感受方面的福利状况处于中间水平,其它功能性指标的福利水平较低。在影响农民工福利的主要因素中,工作环境和防护性保障的改善对提升农民工福利影响最大。运用OLS回归模型对农民工的福利状况进行扩展分析,发现农民工群体内部存在较强的异质性,并且不同特征的农民工群体福利水平相差很大。     

Intraday Serial Correlation,Volatility, and Jump: Evidence from China's Stock Market

In this article, we investigate the relationships among intraday serial correlation, jump-robust volatility, positive and negative jumps based on Shanghai composite index high frequency data. We implement variance ratio test to quantify intraday serial correlation. We also measure the continuous part of realized volatility using jump-robust MedRV estimator and disentangle positive and negative jumps using Realized Downside Risk Measure and Realized Upside Potential Measure proposed by Bi et al., (2013 Bi, T., Zhang, B., Wu, H. (2013). Measuring downside risk using high frequency data–realized downside risk measure. Communications in Statistics–Simulation and Computation 42(4):741–754.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]). We find that intraday serial correlation are positively correlated with jump-robust volatility and negatively correlated with negative jumps which confirm the LeBaron effect.     

Classification with minimum ambiguity under distribution heterogeneity

The traditional classification is based on the assumption that distribution of indicator variable X in one class is homogeneous. However, when data in one class comes from heterogeneous distribution, the likelihood ratio of two classes is not unique. In this paper, we construct the classification via an ambiguity criterion for the case of distribution heterogeneity of X in a single class. The separated historical data in each situation are used to estimate the thresholds respectively. The final boundary is chosen as the maximum and minimum thresholds from all situations. Our approach obtains the minimum ambiguity with a high classification accuracy allowing for a precise decision. In addition, nonparametric estimation of the classification region and theoretical properties are derived. Simulation study and real data analysis are reported to demonstrate the effectiveness of our method.     

A semi-parametric method for estimating the beta coefficients of the hidden two-sided asset return jumps

ABSTRACT

We introduce a new methodology for estimating the parameters of a two-sided jump model, which aims at decomposing the daily stock return evolution into (unobservable) positive and negative jumps as well as Brownian noise. The parameters of interest are the jump beta coefficients which measure the influence of the market jumps on the stock returns, and are latent components. For this purpose, at first we use the Variance Gamma (VG) distribution which is frequently used in modeling financial time series and leads to the revelation of the hidden market jumps' distributions. Then, our method is based on the central moments of the stock returns for estimating the parameters of the model. It is proved that the proposed method provides always a solution in terms of the jump beta coefficients. We thus achieve a semi-parametric fit to the empirical data. The methodology itself serves as a criterion to test the fit of any sets of parameters to the empirical returns. The analysis is applied to NASDAQ and Google returns during the 2006–2008 period.     

中西文论异质性比较研究——新批评在中国的命运

新批评是现代英语学界文学研究中影响最大的一个理论流派,持续时间也最长.但是新批评对中国文论界的影响始终不大.英美新批评与作为中国现代主流文论的马克思主义文论,在意识形态上存在着难以逾越的鸿沟,在艺术理论上也有着鲜明的异质性.中国古代文论带有强烈的印象式批评特点,而新批评则带有强烈的形式主义和科学主义倾向,尽管新批评与中国古代文艺思想之间也有着某种程度上的相通之处,但是两者之间这些强烈和根本的异质性,决定了新批评在中国始终处于边缘化的境遇.     

农村人力资本、空间效应与城乡收入差距

基于2000—2017年的省级面板数据,采用SDM模型来研究异质性农村人力资本对城乡收入差距的空间效应,并进一步分解为直接效应和空间溢出效应进行比较分析。结果表明：（1）我国城乡收入差距存在显著正向空间集聚效应,并且这种空间集聚效应与区域经济发展水平紧密相关;（2）初级、中级、高级农村人力资本的空间集聚效应特征呈现明显空间差异：初级农村人力资本大多数集聚于西部省份,中级农村人力资本大多数集聚于现代农业相对发达的省份,而高级农村人力资本的高集聚区经历了从东北地区向长三角地区的动态转移;（3）中级、高级农村人力资本显著缩小了本地区及邻近地区的城乡收入差距,但中级农村人力资本的作用更大,而初级农村人力资本对城乡收入差距的影响不显著。     

子公司异质性特征对企业集团绩效影响研究述评

传统企业理论将企业集团所属子公司视为无差异整体,但集团下属子公司在行业分布、成立年限、发展规模和能力成熟度等方面存在着显著的差异,这被称之为子公司的异质性特征,这些异质性特征会对集团总部的管理控制造成不同程度的影响。在回顾国内外相关文献的基础上,对子公司异质性特征的内涵、存在必要性、测度方法及子公司异质性与企业集团整体绩效表现的关系进行了系统梳理与总结。基于分析,提出了子公司异质性特征研究的整合模型,并对该领域未来可能的重点研究方向进行了展望。     

异质、冲击与对策：互联网金融与银行业的共生发展--基于博弈视角的分析

互联网金融的崛起,既通过"增量式"改革模式推动我国金融体系的完善和再造,又以"搅局者"异质效应冲击当前金融市场主体,特别是银行业的传统优势。目前,我国互联网金融发展模式相对单一,与银行业相比具有异质性。基于博弈论的视角,有必要加强对互联网金融的监管,充分发挥互联网金融和传统银行业的比较优势,错位竞争,形成互利共生的良性循环。采取多种措施促进互联网金融和传统银行业健康可持续的共生发展。     

重庆市县域商品房价格时空变化特征研究——基于空间统计分析法

以2005—2015年重庆市38个区（县）商品房价格数据为样本,利用空间自相关等空间统计分析方法对重庆市县域商品房价格的空间分布和时空演变特征进行研究。研究结果表明：渝东北地区商品房价格稳定性相对最好,渝西地区次之,渝东南地区再次之,主城区商品房价格稳定性最差;重庆市商品房价格具有较强的空间集聚性,但随着时间的推移,空间集聚性逐渐减弱,商品房价格空间差异逐渐缩小;重庆市商品房价格区域差异呈现明显的空间二元结构,房地产发展热点区域主要集中于主城九区,远郊区县的房地产发展相对缓慢。