A Note on the Role of the Propensity Score for Estimating Average Treatment Effects

Hahn [Hahn, J. (1998). On the role of the propensity score in efficient semiparametric estimation of average treatment effects. Econometrica 66:315-331] derived the semiparametric efficiency bounds for estimating the average treatment effect (ATE) and the average treatment effect on the treated (ATET). The variance of ATET depends on whether the propensity score is known or unknown. Hahn attributes this to “dimension reduction.” In this paper, an alternative explanation is given: Knowledge of the propensity score improves upon the estimation of the distribution of the confounding variables.     

设立村级河长提升农村水环境治理绩效了吗?——基于倾向得分匹配(PSM)的反事实估计

农村水环境长期存在“边治理、边衰退”和地方政府监管乏力问题,通过广泛设立村级河长能促进农村水环境治理绩效的提升吗?基于黄河流域4省份实地调查数据,采用倾向得分匹配法(PSM)实证检验村级河长的设立对农村水环境治理绩效的影响及机制,比较不同流域差异、地理区位及村庄规模下的组群差异。实证结果表明:村级河长的设立能够显著提升农村水环境治理绩效,对上游村庄、中小型村庄、近郊村的水环境治理绩效有显著的提升效应,且稳健性检验后结论依然成立。进一步的机制分析发现,村级河长有效治理的深层原因在于村庄内部知识资源、关系资源、动员能力发挥着中介效应,在政府纵向激励问责机制的驱动下村级河长通过资源整合与策略化动员,有效弥补自身治水资源不足的缺陷,避开低绩效陷阱,进而提升河长制在“最后一公里”的政策效应。     

要素匹配与中国投资效率空间差异性——基于双层嵌套型函数的分解研究

本文基于四要素双层嵌套的生产函数,利用1990-2016年全国层面及省际层面数据测算投资效率,并分析其空间结构特征及演变轨迹,检验投资效率匹配效应影响因素。研究发现：①1990-2016年我国整体投资效率呈下降趋势,资本-技能劳动匹配效应与整体投资效率走势趋同,快速累积的资本存量和不断升级的资本质量与短缺的技能劳动之间矛盾突出。②东中西部地区投资效率增长非一致性明显。东部地区资本相对投资效率明显高于中西部,但下降幅度大于中西部,中西部与东部地区之间差距缩小,其中匹配效应是区域间投资效率非平衡的主要成因。③若产业结构升级的技能劳动需求不能满足,将引发要素错配,不利于有效投资。房价与工资提升分别通过影响技能劳动供给和需求抑制要素匹配效率;教育和公路设施会对地区要素匹配产生积极影响,改善地区间投资效率非均衡性;地区投资效率存在显著正向空间相关性,毗邻地区的要素流动和经济发展相近地区的技术溢出均对投资效率产生积极的影响。     

城市化与产业发展的匹配机制研究--基于比较优势的理论视角

城市化与产业发展是相互促进、互为因果螺旋上升的关系,城市是产业发展的载体,城市化的推进引致巨大的消费需求和投资需求,而产业是城市化的动力和支撑。城市化进程可以看成是资源、基础设施、制度和环境等一系列要素禀赋的动态变化,并在此基础上形成比较优势,吸引特定产业的投资和促进产业演进,在一个静态时点上,城市化与产业发展处于一般均衡状态,二者之间存在一种相互匹配关系。因此,在我国新型城镇化建设中要树立大、中、小不同规模城市协同发展的理念,在分析城市要素动态变化基础上,实施科学有效的产业政策。     

信息化条件下流通商主导的供应链动态联盟

供应链动态联盟是信息技术发达、市场需求主导的条件下实现敏捷生产和流通的重要组织形式。是一种基于非正式契约的不完全市场交易方式。在消费者占据主导权、生产企业逐渐归核化（refkusing）的条件下,流通商在联盟中居于重要地位。文章论述了信息网络技术高度发达的条件下流通商主导的供应链动态联盟的运作机制,以期能够为建立和谐高效的产销关系提供理论支持。     

Objective Bayesian inference for the ratio of the scale parameters of two Weibull distributions

The Weibull distribution is widely used due to its versatility and relative simplicity. In our paper, the non informative priors for the ratio of the scale parameters of two Weibull models are provided. The asymptotic matching of coverage probabilities of Bayesian credible intervals is considered, with the corresponding frequentist coverage probabilities. We developed the various priors for the ratio of two scale parameters using the following matching criteria: quantile matching, matching of distribution function, highest posterior density matching, and inversion of test statistics. One particular prior, which meets all the matching criteria, is found. Next, we derive the reference priors for groups of ordering. We see that all the reference priors satisfy a first-order matching criterion and that the one-at-a-time reference prior is a second-order matching prior. A simulation study is performed and an example given.     

Some practical issues in the evaluation of heterogeneous labour market programmes by matching methods

Summary.  Recently several studies have analysed active labour market policies by using a recently proposed matching estimator for multiple programmes. Since there is only very limited practical experience with this estimator, this paper checks its sensitivity with respect to issues that are of practical importance in this kind of evaluation study. The estimator turns out to be fairly robust to several features that concern its implementation. Furthermore, the paper demonstrates that the matching approach per se is no panacea for solving all the problems of evaluation studies, but that its success depends critically on the information that is available in the data. Finally, a comparison with a bootstrap distribution provides some justification for using a simplified approximation of the distribution of the estimator that ignores its sequential nature.     

`Sex-Equal' Stable Matchings

The paper defines a measure on the set of stable matchings in the marriage problem. This measure is based on the minimization of the envy difference between the sets of men and women, while preserving stability and selects stable matchings with the least conflict of interest between both groups of agents. The solution concept proposed is called Sex-equal Matching (SEM) and the paper also provides an algorithm to compute the set of SEM.     

企业信息化工程中的匹配理论及映射模型研究

通过对中国企业信息化工程现状的分析,指出先进的信息系统与企业管理基础之间存在较大的差距是项目成功率不高的主要原因,提出企业管理系统与信息系统匹配理论,详细阐述了匹配理论的内容和原则,围绕匹配度测算问题,建立了映射模型,定义了映射函数和映射法则。     

婚姻匹配结构与主观幸福感——来自中国大样本微观数据的实证研究

本文利用2006年中国综合社会调查（ CGSS ）数据,研究首次婚姻中,夫妻个人经济状况匹配和家庭经济状况匹配的不同组合与婚后生活幸福感之间的关系。本文发现,无论是男性还是女性,在控制了年龄、年龄的平方、受教育年限、民族、政治面貌、户口、宗教信仰、工作满意程度、个人健康满意程度、人际关系满意程度、住房状况、家庭经济状况、家庭关系满意程度以及省份哑变量等变量的情况下,相对于“门当户对”,家庭经济状况为“男低女高”婚配结构的生活会更幸福。在分组回归中,本文进一步发现,以“个人经济状况和家庭、经济状况同为门当户对”作为基准组,“个人经济状况为门当户对,且家庭经济状况为男低女高”的婚配结构会更幸福。如果家庭经济状况为“男低女高”是男女双方为了追求爱情而冲破传统“门第”观点的结果,那么,本文发现的引申含义是基于爱情的婚姻会更幸福。