The Food (In)Security Impact of Land Redistribution in South Africa: Microeconometric Evidence from National Data

The South African land-reform program has been widely criticized for its slow pace as well as its apparent lack of contribution to poverty reduction. No econometric evidence of the impact of land transfers has been provided to date and this paper attempts to fill this gap by considering the impact of receiving a land grant on households’ food insecurity. Propensity score matching and univariate probit estimates using two national household surveys indicate that, on average, land grant recipients are more food insecure than comparable non-participants. Recursive bivariate probit estimates suggest that selection bias is not driving this result.     

墙体参数模糊下穿墙雷达运动目标成像

针对墙参数模糊条件下运动目标成像速度慢、墙参数重建精度差等问题,提出了一种改进拟牛顿-粒子群优化(Limited Broyden Fletcher Goldfarb Shanno-Particle Swarm Optimization,LBFGS-PSO)算法,建立了LBFGS-PSO算法模型,解决了传统拟牛顿算法和粒子群算法计算速度慢、误差较大等问题。该算法与块正交匹配追踪（Block Orthogonal Matching Pursuit,BOMP）算法相结合不仅可以精确重建边墙位置,还能够准确地重建多径效应环境中的运动目标和静止目标,算法的计算速度和精度得到了一定程度的提高。仿真结果和数据分析验证了所提方法的性能。     

“一带一路”倡议能否提升对外直接投资企业盈利能力？

基于2011-2015年A股上市公司与商务部《境外投资企业（机构）名录》数据，利用倾向得分匹配方法（PSM）和双重差分法（DID）考察“一带一路”倡议对中国对外直接投资企业盈利能力的影响及作用机制。研究发现：“一带一路”倡议显著提升了中国对沿线国家投资企业的盈利能力。机制检验表明，“一带一路”倡议能够通过推进中国与沿线国家间的经济融合和文化包容来提升对外投资企业的盈利能力，而政治互信在样本期内不显著。进一步研究发现，“一带一路”倡议对企业盈利能力的提升作用主要体现在国有企业、新兴优势产业以及投资目的为非邻近中国的“一带一路”国家上。     

Estimating matching functions when recruiting intensity matters

The article estimates matching functions – the relationships between new hires, job vacancies and unemployment – using monthly time series data for Sweden. The data contain rich information on types of job vacancies which provides information on firms’ recruiting efforts. The analysis shows that the aggregate flow of new hires is well explained by an augmented version of a standard matching function that incorporates data on firms’ recruiting intensity.     

The German labor market during the Great Recession: Shocks and institutions

This paper analyzes Germany's unusual labor market experience during the Great Recession. We estimate a general equilibrium model with a detailed labor market block for post-unification Germany. This allows us to disentangle the role of institutions (short-time work, government spending rules) and shocks (aggregate, labor market, and policy shocks) and to perform counterfactual exercises. We identify positive labor market performance shocks (likely caused by labor market reforms) as the key driver for the “German labor market miracle” during the Great Recession.     

Impacts of sustainability certification on farm income: Evidence from small-scale specialty green tea farmers in Vietnam

Sustainability certification for small-scale farms has gained considerable momentum in developing countries. However, evidence on the economic benefits of certification schemes in the context of domestically consumed foods and beverages is scarce. This paper addresses this gap by evaluating the impacts of sustainability standards on the selling prices, sales, costs and net income of small-scale specialty green tea farming in Vietnam. We analyze original survey data on 401 smallholder green tea farmers and employ propensity score matching to mitigate self-selection bias. Our estimates reveal that certified green tea producers are able to obtain a higher average selling price and sales value. In addition, although certification leads to a dramatic increase in the costs of hired labor, net farm income is still significantly improved.     

The role of fundamental motivations in willingness-to-pay online

This study aims to determine whether an understanding of chronic fundamental consumer motivations can help determine the mechanisms of willingness-to-pay for products online. To do so, it employs a simulated buying task on a fictional e-commerce site for a consumer product (branded either as a “new arrival” or a “classic”) to investigate the effects of two fundamental motivations (mate acquisition vs. self-protection) on willingness-to-pay for the product online. The primary focus of the paper to investigate the capacity of mate acquisition and self-protection motives to moderate the relationship between attitude toward the product and willingness-to-pay, as well as, the effects of the motives on willingness-to-pay are considered. Through regression and interaction effect analyses, it is shown that chronic fundamental motivation for mate acquisition is directly correlated with an increased willingness-to-pay for both product types, and it moderates the relationship between attitude toward a product and willingness-to-pay. Self-protection motivation increases willingness-to-pay for classic products but not new arrivals. By offering a rare look at chronic fundamental motivation in the consumer context and potentially being the first investigation of the moderating effects of fundamental motivations, the results mostly support the notion of predictable motivation induced behavioral tendencies.     

设立国家级贫困县能提升当地农民收入水平吗——基于2007~2016年中国296个县面板数据的实证研究

中国自1986年实施贫困县制度以来，国家级贫困县的设立是否能够以及在多大程度上提升了当地农民实际收入水平，需要进行系统科学的实证检验。基于双重差分倾向得分匹配法（PSM-DID），利用2007~2016年全国6个省份296个县的面板数据进行实证研究发现，国家级贫困县的设立非但没能有效提升当地农民实际收入水平，反而对其有持续的负效应。进一步研究发现，贫困地区第二、三产业的发展能够有效提高当地农民实际收入水平，然而贫困县政策并未促进当地产业结构的优化；政府通过正向干预农产品价格能有效增加农民实际收入。从研究结论的政策含义讲，立足贫困户推进精准扶贫、通过招商引资带动有效投资，以及优化县域产业结构，对于提升贫困县的农民收入具有重要现实意义。     

财权和事权相匹配关系研究

在政府间财政关系中,财权和事权的匹配是主要的财政关系之一,明确财权和事权的划分,保证财权和事权相匹配是我国财税改革的关键。然而,当前政府间财权和事权划分不明确,导致了财权上移、事权下放等问题,没有达到真正意义上的匹配。文中在此回顾各方意见,总结政府间财权与事权的理论依据和存在的问题,并对现阶段的改革对政府间财权事权关系的影响做了简要评述。     

A context-based service matching approach towards functional reliability for industrial systems

ABSTRACT

As service-oriented computing is commonly used in industrial systems to deal with the continually changing business environment, matching processes with existing services becomes one of the most important phases in constructing, integrating and optimizing information systems. The precision of semantic service matching becomes a critical factor in ensuring the correctness of functionalities in system processes. However, the dependability of semantic service matching cannot be warranted in complex contexts. To improve semantic service matching for industrial systems, a context-based semantic service matching approach named ‘Process-Based service MatchMaker’(PBMM) is proposed in this paper. It selects the suitable services for the process from candidate services through taking the dependencies of related services process into consideration.