我国制造业企业国内价值链嵌入度的测算与事实

尽管国内价值链战略被视为助推中国产业发展的重要途径,但受制于忽略异质性的不足,已有研究很难进行企业层面的系统分析。有鉴于此,本文通过汲取增加值贸易与微观计量的双重优势,整合2002年、2007年、2010年、2012年省(区、市)间投入产出数据、工业企业数据与海关数据的海量信息,构建了一个可以连接新新贸易理论与国内价值链的分析框架。结果显示:我国制造业的国内价值链嵌入度大幅提升,但是提升背后隐藏着偏好加工制造、排斥服务投入的倾向;进一步考虑贸易类型、区域空间与所有制差异,也未改变国内价值链嵌入度的上述倾向;由于在位效应(存活企业的平均加权变动)构成了国内价值链嵌入度偏向加工制造、排斥服务投入的主要原因,我国制造业的国内价值链整合存在着循环累积的低端陷阱。本文的以上发现不仅补充了国内价值链的研究框架,同样为推动我国制造业高质量发展提供了切实参考。     

异质性企业的空间选择与地区生产率差距研究

 本文在融入企业异质性的空间经济学理论框架下,采用中国工业企业数据库微观数据,运用分位数回归的方法,检验异质性企业的空间选择与产业集聚效应对地区(企业)生产率差距的影响程度。结果表明：（1）异质性企业的定位选择行为在中国显著存在,并且是影响地区（企业）生产率差距的另一重要的微观机制;（2）在中国,地区产业集聚并没有对本地企业生产率产生正向影响,即集聚效应并不明显。     

考虑截面相关条件下的异质性面板数据协整回归模型的估计

 面板数据的非平稳分析是近年来迅速发展的方向,其中考虑截面相关情形下面板数据的协整分析的发展备受关注。Bai &; Kao（2006）得出了截面相关条件下面板协整估计的因子模型,但该模型只考虑了被解释变量截面相关情形,未考虑解释变量的截面相关,且假定各截面间长期协方差矩阵相同。本文在Bai（2006）考虑截面相关条件下面板数据协整回归模型估计的基础上将其结论推广至被解释变量和解释变量均截面相关及截面长期协方差矩阵不相同即异质性时的情形,并试图通过Monte Carlo 模拟讨论其小样本性质。并且由于截面间长期协方差矩阵异质性的存在,本文还针对两变量的协整系统提出了系数检验的组间均值t统计量。     

Bayesian Analysis of Poisson Regression with Lognormal Unobserved Heterogeneity: With an Application to the Patent-R&D Relationship

This article considers explicit and detailed theoretical and empirical Bayesian analysis of the well-known Poisson regression model for count data with unobserved individual effects based on the lognormal, rather than the popular negative binomial distribution. Although the negative binomial distribution leads to analytical expressions for the likelihood function, a Poisson-lognormal model is closer to the concept of regression with normally distributed innovations, and accounts for excess zeros as well. Such models have been considered widely in the literature (Winkelmann, 2008 Winkelmann , R. ( 2008 ). Econometric Analysis of Count Data. , 5th ed. Berlin : Springer . [Google Scholar]). The article also provides the necessary theoretical results regarding the posterior distribution of the model. Given that the likelihood function involves integrals with respect to the latent variables, numerical methods organized around Gibbs sampling with data augmentation are proposed for likelihood analysis of the model. The methods are applied to the patent-R&D relationship of 70 US pharmaceutical and biomedical companies, and it is found that it performs better than Poisson regression or negative binomial regression models.     

生命周期中教育收益率变动轨迹分析

有很多使用长期面板数据的研究指出,当期收入与终身收入并不平行,表明教育收益率在生命中的不同时期可能是有差异的。认识教育收益率的异质性是有效制定相关政策的基础,也是研究领域非常关注的问题,但是很少有研究分析教育收益率在生命周期中的异质性。本研究使用中国家庭健康与营养调查面板数据以及多水平分析方法,探讨了教育收益率在生命周期中的变动轨迹,并进行了性别差异分析。研究发现：教育收益率在整个生命周期中呈现先上升后下降的倒U型分布,在初期为负值;在生命周期前期女性的教育收益率大于男性,后期是男性大于女性;教育水平越高,收入增长所持续的时期越长。     

异质性数据下广义线性模型的Maximin似然比估计及应用

针对具有多个来源的异质性数据,文献中通常提出复杂程度较高的模型用于描述每个数据子总体的特征,而本文着眼于刻画不同数据子总体的共性进而建立一个简单的模型。在参数估计方面,本文借鉴了普通线性模型的Maximin估计思想,提出了适用于广义线性模型的Maximin似然比估计方法及稀疏结构下的惩罚估计。该方法通过最大化所有子总体中似然比统计量的最小值,构建成一个简单而保守的模型,以减少数据来源较多而呈现的复杂性。所提方法适用于因变量服从正态分布、两点分布、泊松分布等指数族分布的情形,丰富了前人的研究成果,具有更好的实践意义。模拟分析显示,相比于经典的估计方法,Maximin似然比估计方法不仅能够有效地探寻子总体的共性,而且具有较高的样本外预测精度。本文提出的方法也适用于政府统计和经济统计中具有异质性的大型数据集。     

货币政策加剧城市房价的冷热不均吗

本文创新性地运用交互效应动态面板模型重新检验了货币政策对我国295个城市房价的异质性效应及其传导机制。研究发现,货币供给量增长对我国不同城市房价存在显著的异质性效应,货币供给量是加剧我国城市房价结构性分化的主要外部诱因,而利率调整发挥的作用并不明显。机制分析则表明,货币政策冲击主要通过供给侧的土地价格这一传导渠道对房价产生影响。本文研究认为,央行在制定货币政策,尤其是运用数量型工具时应将城市住房价格考虑在内,政府应切实推动土地市场改革,才有可能真正解决我国房地产市场的结构性分化难题。     

Heterogeneity of Cancer Risk Due to Stochastic Effects

Persons with exactly the same genetic background, behavior, environment, etc. may have differences in cancer risk due to a different number of cells on the way to malignancy. These differences are estimated quantitatively by using the two-stage clonal expansion model. For liver cancer the estimated relative risk for persons without intermediate cells at age 40 is less than 10% when compared to the risk of the total population, while the top 0.1% risk group has a more than 100-fold risk compared to the population. The risk of the 1% percentile in risk is more than 100-fold of the risk of the more than 95% persons without intermediate cells. The number of intermediate (premalignant) cells in the risk groups cannot be calculated from incidence data only because they depend strongly on a nonidentifiable parameter. But under plausible assumptions, less than about 1,000 intermediate cells are present at age 40 even in high-risk persons.     

家庭视角下牧民城乡流动的异质性分析——来自内蒙古阿巴嘎旗的田野调查

人口流动是我国新时代城乡关系塑造的重要内容。通过对典型牧区内蒙古阿巴嘎旗的实地调研发现,牧民城乡人口流动与传统农民城乡流动不同,呈现"牧作城居、周期往返"的家庭分离特点。牧民城乡流动异质性与制度政策、收入水平、文化社会和生态环境等多种因素紧密相关。     

Moran's I statistic-based nonparametric test with spatio-temporal observations

Moran's I statistic [Moran, (1950), ‘Notes on Continuous Stochastic Phenomena’, Biometrika, 37, 17–23] has been widely used to evaluate spatial autocorrelation. This paper is concerned with Moran's I-induced testing procedure in residual analysis. We begin with exploring the Moran's I statistic in both its original and extended forms analytically and numerically. We demonstrate that the magnitude of the statistic in general depends not only on the underlying correlation but also on certain heterogeneity in the individual observations. One should exercise caution when interpreting the outcome on correlation by the Moran's I-induced procedure. On the other hand, the effect on the Moran's I due to heterogeneity in the observations enables a regression model checking procedure with the residuals. This novel application of Moran's I is justified by simulation and illustrated by an analysis of wildfire records from Alberta, Canada.