Minimum average risk estimators for coefficients in linear models

We consider the problem of estimating the coefficient vector β of a linear regression model with quadratic loss function. Some biased estimators which utilize the prior information about β are considered. Also studied is the problem of estimating the parameters of an over-identified structural equation from undersized samples.     

异质机构投资者、实地调研与公司财务重述行为

上市公司真实、准确地履行财务信息披露责任,对于保护投资者权益、稳定资本市场具有重要意义。基于2013—2020年中国深圳证券交易所A股上市公司数据,考察了异质机构投资者对公司财务重述行为的影响。研究发现,同交易型机构投资者相比,稳定型机构投资者显著抑制了公司财务重述行为,实地调研则强化了上述抑制作用。机制分析表明,稳定型机构投资者通过改善公司信息环境、提高内部控制水平发挥抑制作用。进一步研究发现,稳定型机构投资者对技术问题型和非技术问题型财务重述行为、欺诈型和非欺诈型财务重述行为均有抑制作用,但实地调研仅强化了对非技术问题型和非欺诈型财务重述行为的抑制作用。因此,监管部门应积极引入稳定型机构投资者,完善投资者实地调研的相关制度,从而形成对上市公司会计信息质量的有效外部监督。     

Multivariate linear regression for heterogeneous data

The problem of multivariate regression modelling in the presence of heterogeneous data is dealt to address the relevant issue of the influence of such heterogeneity in assessing the linear relations between responses and explanatory variables. In spite of its popularity, clusterwise regression is not designed to identify the linear relationships within ‘homogeneous’ clusters exhibiting internal cohesion and external separation. A within-clusterwise regression is introduced to achieve this aim and, since the possible presence of a linear relation ‘between’ clusters should be also taken into account, a general regression model is introduced to account for both the between-cluster and the within-cluster regression variation. Some decompositions of the variance of the responses accounted for are also given, the least-squares estimation of the parameters is derived, together with an appropriate coordinate descent algorithms and the performance of the proposed methodology is evaluated in different datasets.     

Heterogeneous data modeling with two-component Weibull–Poisson distribution

The mixture distribution models are more useful than pure distributions in modeling of heterogeneous data sets. The aim of this paper is to propose mixture of Weibull–Poisson (WP) distributions to model heterogeneous data sets for the first time. So, a powerful alternative mixture distribution is created for modeling of the heterogeneous data sets. In the study, many features of the proposed mixture of WP distributions are examined. Also, the expectation maximization (EM) algorithm is used to determine the maximum-likelihood estimates of the parameters, and the simulation study is conducted for evaluating the performance of the proposed EM scheme. Applications for two real heterogeneous data sets are given to show the flexibility and potentiality of the new mixture distribution.     

An Empirical Study of Statistical Properties of Variance Partition Coefficients for Multi-Level Logistic Regression Models

Partitioning the variance of a response by design levels is challenging for binomial and other discrete outcomes. Goldstein (2003 Goldstein , H. ( 2003 ). Multilevel Statistical Models. 3rd ed . London : Edward Arnold . [Google Scholar]) proposed four definitions for variance partitioning coefficients (VPC) under a two-level logistic regression model. In this study, we explicitly derived formulae for multi-level logistic regression model and subsequently studied the distributional properties of the calculated VPCs. Using simulations and a vegetation dataset, we demonstrated associations between different VPC definitions, the importance of methods for estimating VPCs (by comparing VPC obtained using Laplace and penalized quasilikehood methods), and bivariate dependence between VPCs calculated at different levels. Such an empirical study lends an immediate support to wider applications of VPC in scientific data analysis.     

企业利用FTA出口的影响因素分析

当前,以FTA为代表的区域贸易协定正逐渐成为各国开展经济战略合作与竞争的重要手段,但是现实中我国企业对FTA的利用率并不高。为了探寻其中的原因,首先从FTA使用成本和收益的角度建立了一个分析影响企业FTA利用率的理论模型,探讨了企业FTA策略选择背后的作用机制。其次,基于2017年中国—东盟FTA的问卷调查数据,利用有序probit模型进行了实证研究,发现企业获取FTA信息的难易程度、申请原产地证书的时间等FTA使用成本是影响中国企业FTA利用率的重要因素;利用FTA出口则有助于企业增加出口量,使其出口产品更具价格优势,并有助于企业加入全球/区域生产网络和产品供应链。最后,异质性检验结果表明,相对于生产型企业,获取FTA信息困难程度的降低、企业申请原产地证书时间的缩短等更有利于提高外贸型企业的FTA利用率;大规模企业对FTA的利用率受FTA使用所得收益的影响较大,而小规模企业对FTA的利用率则对FTA使用成本更为敏感。为了提高企业对FTA的利用率,政府应当扩大对FTA相关政策的宣传,提高企业的认知水平,同时简化各种审批手续,努力缩短原产地证书申请所需时间。     

城市人力资本外部性的识别——基于工业企业生产率视角的研究

人力资本外部性的存在具有重要的现实意义,它是政府进行教育投资和人力资本投资的重要决策依据.文章从工业企业生产率视角识别城市人力资本外部性,基于中国工业企业微观数据、人口普查分县资料和地级市统计数据,考虑城市人力资本变量的内生性后,采用两阶段最小二乘法,实证研究城市人力资本对工业企业生产率的影响.研究发现:在控制企业自身的人力资本后,城市大专以上学历人口占比越高,工业企业的产出越高,人力资本的溢出效应显著,且人力资本正外部性主要存在于人口规模300万以上的大城市.从工业内部看,行业内人力资本正外部性随城市规模扩大逐渐增强,而行业外人力资本正外部性随城市规模扩大逐渐减弱.从企业异质性看,高新技术企业、非国有企业和大企业从城市人力资本提高中获得的正向溢出效应更大.此外,城市外商直接投资和地方政府财政支出越高,地理区位距离港口越远,越不利于工业企业产出的提高.文章的研究结论表明增加人力资本投资,促进人力资本结构升级,发挥大城市人力资本溢出效应对新时期经济可持续增长尤为重要.     

异质性技术创新对碳强度的影响——基于全球专利数据

基于全球专利数据库（PATSTAT）,采用高价值专利统计方法,测算各国在汽车、燃料、照明和能源生产四大领域内清洁技术和污染技术的创新水平;再利用1996-2011年全球15个经济体的面板数据,分析不同类别技术创新对碳强度的影响。实证结果显示:在汽车、燃料、照明和能源生产4个领域内,中国清洁技术和污染技术的创新指标皆呈现出上升趋势,且前者提升速度更快。不同类别技术创新对碳强度的影响存在差异,即清洁技术创新存在显著的抑制作用,污染技术创新存在显著的促进作用,且碳强度变化对后者的敏感性更高。为了避免清洁技术创新的碳强度抑制效果被污染技术创新所抵消,有必要将经济资源更多地配置于清洁技术研发活动中,并逐步消除对污染技术创新的政策支持。     

一类变系数边值问题的样条解法

本文讨论了一类三阶变系数微分方程的边值问题的样条解法．构造了一个四次样条的近似解,并证明了它的唯一性和收敛性．在文末举例说明本方法是可行的．