Local poverty reduction in Chile and Mexico: The role of food manufacturing growth

This paper analyzes the relationship between local poverty and food manufacturing growth in Chile and Mexico using propensity score matching, differences in differences and spatial econometrics methods. We focus on food manufacturing as a sector with a number of characteristics that make it potentially pro-poor, and whose incentives for spatial distribution may either strengthen or dampen its poverty reduction potential. The overall results indicate growth in food manufacturing employment contributes to local poverty reduction.     

Using social networking websites as a selection tool: The role of selection process fairness and job pursuit intentions

A growing trend in the hospitality industry is openly encouraging applicants to join their social networking sites as part of their recruitment process (0080 and 0185). However, there is a dearth of studies examining how applicants perceive and react to the use of social networking websites in the recruitment and selection process. Therefore, the purpose of the current study was to examine how applicants react to the use of social networking websites as a selection tool. Using experimental methods, participants attending a career fair for hospitality jobs completed a questionnaire after reading about a hospitality company that does or does not use social networking sites in the selection process. The results showed that perceived fairness and job pursuit intentions of applicants were lower for an organization that used social networking websites as a selection tool than an organization that did not use social networking websites as a selection tool.     

球类竞赛的排各式积分编排方法研究

在球类竞赛中,采用“分组循环＋淘汰赛”的竞赛办法,虽然可以解决赛程适中的问题,但不能解决分组的问题。而棋类积分编排赛制虽然可以避免分组,但由于受到职业等级分排序的局限,使得其它项目的竞赛编排无法参照。通过研究,借鉴棋类积分编排方法理论,我们总结出“排名式积分编排方法”理论。目的是把棋类积分编排方法运用到其他体育项目上。虽然该理论目前还没有在积分编排软件上得到运用,但可以为研究人员提供参考。     

Tuition fees and social segregation: lessons from a natural experiment at the University of Paris 9-Dauphine

Using a natural experiment, a sharp rise in tuition fees in some of the programmes at the University of Paris 9-Dauphine, we study the impact of tuition fees on students’ pathways, and outcomes. We apply an optimal matching method to the national database of students’ registrations (SISE) to define a typology of pathways. We then use a nonordered multinomial logit model to evaluate the impact of the rise in tuition fees on the types of pathways selected by the university. We show that there is a significant impact on these pathways. The increase in tuition fees reduces geographic and social mobility, thereby accentuating the phenomena of social segregation. Furthermore, contrary to what some of the studies assert, the rise does not appear to encourage greater effort: we find no impact on the graduation success rate.     

基于SBO-PP模型的水资源可持续发展能力评价模型及应用

为利用投影寻踪(PP)技术科学,客观评价区域水资源可持续发展能力,基于生态环境、水资源和经济社会因素选取20个指标构建区域水资源可持续发展能力评价指标体系。利用新型仿生群体智能算法——凉亭鸟优化(SBO)算法优化PP技术最佳投影方向,提出SBO-PP水资源可持续发展能力评价模型,并构建灰狼优化(GWO)算法-PP模型、人工蜂群(ABC)算法-PP模型、差分进化(DE)算法-PP模型、地理生物学优化(BBO)算法-PP模型、粒子群优化(PSO)算法-PP模型作对比,以云南省2006—2015年及2020年水资源可持续发展能力评价为例进行实例研究。结果表明:SBO算法优化PP技术获得的适应度值优于GWO、ABC、DE、BBO和PSO算法,具有较好的求解精度、稳健性能和极值寻优能力。SBO-PP模型对云南省2006—2007年水资源可持续发展能力评价为"较差",2008—2015年评价为"中等",2020年评价为"较强"。     

基于投影寻踪方法的粮食主产区农民用水合作组织绩效研究——基于湖北、湖南、黑龙江3省的调查

[目的]农民用水合作组织是我国灌溉管理制度改革的产物,农民用水合作组织的建立改进了农村水利管理的方式,提高了灌溉管理过程中水资源的利用率。[方法]通过构建粮食主产区农民用水合作组织绩效评价指标体系,建立基于实数编码加速遗传算法的投影寻踪分类模型,对湖北、湖南、黑龙江等3省61家农民用水合作组织的绩效进行了实证分析。[结果]粮食主产区农民用水合作组织绩效水平总体较好,在所调查的61家农民用水合作组织中,27.1%的农民用水合作组织绩效为优秀,28.8%绩效良好,13.6%绩效一般,30.5%绩效较差。[结论]总体上来看,湖南、湖北等2省农民用水合作组织的绩效高于黑龙江。是否有产权、农户参与率、是否民主决策、培训次数、农户满意度、单位面积灌水量和水费收取率等指标对农民用水合作组织绩效影响最大。因此,政府适当放权,选取恰当的扶持方式,提升农户的认识,推广好的农民用水合作组织发展模式是提高农民用水合作组织绩效的有效途径。     

区域产业发展视角的农业综合开发影响评估——基于对蔬菜产业的干预效应分析

【目的】通过定量方法准确评估农业综合开发对区域优势产业发展的影响有重要意义。【方法】从农业综合开发对蔬菜产业的项目干预效应入手,以县级为单位,将当年农业综合开发项目扶持内容包括蔬菜产业的县级单位划分为干预组,其他为控制组。采用可以有效解决样品选择偏差的倾向得分匹配方法,通过引入协变量、平衡检验、匹配等步骤,在控制组中找到与干预组成员单位特征相似的成员,构建反事实研究框架。【结果】结果得出,项目干预组比控制组区域的蔬菜播种面积占比高出1~3个百分点,说明农业综合开发项目对蔬菜产业的扶持对蔬菜播种面积的扩大有促进作用,利于蔬菜产业壮大。通过协变量影响力分析得出,地区的蔬菜生产优势是最重要的影响因素,从侧面证明了农业综合开发项目的扶持方向紧跟区域优势的政策宗旨。【结论】可见,通过有方向性的农业综合开发项目实施扶持特定产业对促进区域优势产业发展和实现农业结构优化是有效的。     

广义空间调制系统的正则化OMP检测算法

在广义空间调制（GSM）系统中,最大似然（ML）检测可以取得最优的检测性能,然而其计算复杂度随激活天线数的增加急剧增长。针对这一问题,提出了一种基于稀疏重构理论的低复杂度检测算法——正则化正交匹配追踪（ROMP）算法。该算法首先根据信道矩阵和当前残差的内积选取多个候选激活天线索引,接着对候选天线索引按正则化标准进行可靠性验证,剔除错误索引,缩小信号的搜索空间,最后通过求解最小二乘问题估计信号。仿真结果表明,与经典的正交匹配追踪（OMP）算法相比,所提算法以少许复杂度的增加为代价极大提升了检测性能,能够在检测性能与复杂度之间取得更好的折中。     

The effects of exports on facility environmental performance: Evidence from a matching approach

This paper employs matching techniques to investigate the effects of facility export status on environmental performance. Using facility-level criteria air emission data in the US manufacturing industry, we find the industry-specific effects of export status on emission intensity, measured by emissions per value of sale. In some industries, there is consistent and robust evidence supporting the superior environmental performance of exporters relative to non-exporters in terms of emission intensity for all criteria air pollutants tracked. In other industries, we find weak evidence that exporters appear to have a higher emission intensity than non-exporters. This industrial heterogeneity in the effects of exporting on the environment is closely related to industrial characteristics including pollution abatement capital expenditure, trade costs, capital intensity and others.     

旅游区域的城市与景区空间匹配及其实践意义

城市和景区是区域旅游网络中两个基本节点,它们之间关系紧密,包含多种空间匹配关系。数量关系上由一对一匹配、一对多匹配、多对一匹配、多对多匹配构成;等级关系上由正位匹配和倒位匹配构成;距离关系上由城区城郊型、一日游型、离散型构成;几何分布关系上由点轴匹配和面状匹配构成;管理匹配关系上由同位管理匹配和异位管理匹配构成。分析城市与景区空间匹配组合特征,对于寻找合理的景区依托城镇、采取正确的区域旅游发展战略等都具有重要的实践意义。