基于DPSIR-TOPSIS模型的耕地资源环境承载力分析以安徽省颍上县为例

目的 通过测算县域尺度耕地资源环境承载力,为耕地数量、质量与生态“三位一体”保护提供参考,为农业绿色高质量发展提供支撑。方法 文章根据DPSIR模型构建安徽省颍上县耕地资源环境承载力的评价指标体系,并采用改进的TOPSIS方法与障碍度模型,测算了2010—2019年安徽省颍上县耕地资源环境承载力指数并识别了制约当地资源环境承载力的障碍因子。结果 （1）2010—2019年从承载力指数看,颍上县耕地资源环境承载力总体呈现出“波浪式”上升的态势。其中,2010—2013年耕地资源环境承载力指数0.36下降至0.33;2014—2019年耕地资源承载力指数从2014年0.41上升至2019年0.70,承载力水平实现了从中级向良好的转变。（2）从障碍因子看,影响耕地资源环境承载力的关键因子由高标准农田比例、农药施用强度、土壤有机质平均值、免耕面积比转变为人均农业产值产出、人均耕地面积、土壤pH。结论 颍上县耕地资源环境承载力目前处于良好水平,同时在基础设施、体制机制等方面还有提升空间,为此提出以下政策建议：（1）加快高标准农田建设,提升耕地产能。（2）科学合理利用耕地,推进农业绿色发展。（3）加强土壤环境监测与治理,建立耕地保护的激励与管控机制。     

A critical evaluation of alternative methods and paradigms for conducting mediation analysis in operations management research

Mediation as a theory testing approach has witnessed considerable adoption among Operations Management (OM) researchers. Although mediation-testing methods have evolved tremendously in the past decade, their dissemination in the OM field has not seen parallel growth. These advanced techniques facilitate the testing of existing and complex hypotheses in a more precise manner. With the intent of critically evaluating existing and alternative methods for conducting mediation analysis needed to support sophisticated empirical research, this paper first reviews OM studies that tested for mediation in the past eleven years (2002–2012) from top-tier OM journals. Four commonly used mediation approaches were identified. Based on principles of good theory building, type of mediation model, and properties of empirical data, we evaluate the existing methodologies and make recommendations on how to improve the rigor of OM mediation testing. Using published OM studies in top journals as examples, we then illustrate the relevance and advantages of these recommendations, as well as their ease of use. Furthermore, we empirically show that more robust and insightful results can be achieved by adopting these techniques, which in turn have the promise of leading to better theory building and testing in the field of operations management.     

A Field Experiment in Charitable Contribution: The Impact of Social Information on the Voluntary Provision of Public Goods

We study the effect of social information on the voluntary provision of public goods. Competing theories predict that others' contributions might be either substitutes or complements to one's own. We demonstrate a positive social information effect on individual contributions, supporting theories of complementarities. We find the most influential level of social information is drawn from the 90th to 95th percentile of previous contributions. We furthermore find the effect to be significant for new members but not for renewing members. In the most effective condition, social information increases contributions by 12% ($13). These increased contributions do not crowd out future contributions.     

Ecological footprint of Gansu Province, China between 1997 and 2002： changes and inducement

The calculation of Ecological Footprint （EF） on the basis of Input-Output model （I-O model） was advanced by Bicknell, and modified and improved hy Ferng who corrected the footprint＇s aggregation to each sectors. For the lack of sufficient teehnique to deal with the trade between the research areas and the rest of the world, it it necessary to improve this method. And a dynamic analysis of the change of footprint based on I-O model, which could explore the factor impacting the footprint using the ,special advantage of I-O model, ought to be put into practice. After introducing the new method in detail, we calculate and compare the EF and the change of Gansu Province in the northwest of China in 1997 and 2002. The result shows that there was an increase of EF in 2002 caused by final domestic demand. Further; the inerement in EF export was 2.0 × 10^5 ha and 1.6 × 10^6 ha in import. The out-of- region support dropped from 22.6% to 18. 6%. We introduce three factors causing the EF change based on the character of I-O model： the productivity of the resourve which is explained by the change of resource used to obtain one unit output in a sector, the improvement of the economics and the final demand. Finally, we find that the effects of the three factors on the EF change are not identical except the industry sectors and the change of factors in the agriculture and the industry sectors works notably.     

人工智能时代个性化定价行为的反垄断规制--从大数据杀熟展开

人工智能时代,数据规模显著扩张,算法能力持续优化。科技实力雄厚、市场力量强大的经营者凭借大数据与算法工具的紧密结合,收集和分析能够反映消费者特征和行为的相关信息,以无限接近消费者购买能力和支付意愿上限的方式对消费者实施个性化定价。个性化定价行为涉及对条件相同的交易相对人在交易价格上实施差别化待遇,可能构成反垄断法所禁止的价格歧视行为。但与以往反垄断实施重点关注的排他性价格歧视不同,个性化定价突出表现为直接针对终端消费者实施的剥削性价格歧视,且在具体情形下呈现出不同的限制竞争效果,引发消费者选择能力与选择范围的双重限制。鉴于此,个性化定价行为的反垄断规制需要准确识别涉案行为,综合判断竞争效果,慎重选择福利标准。对于同时降低消费者剩余和社会总福利的个性化定价行为,可认定其具有限制竞争效果且不具备正当理由,从而构成违法价格歧视;对于降低消费者剩余却提高社会总福利的个性化定价行为,如果选择消费者福利标准则可认定其构成违法价格歧视,如果选择社会总福利标准则可认定其具备正当理由;对于同时提高消费者剩余与社会总福利的个性化定价行为,因涉及消费者之间的剩余转移,对其竞争效果的评价仍待反垄断实施予以明确。     

房地产基本估价方法比较研究

鉴于人们在进行房地产估价的实际操作中,对采用不同估价方法所得出的结果存在差异及采用什么估价方法存在困惑的缘故,文章将市场比较法、成本法、收益法进行比较,找出其差异与关联性,有助于更好地理解房地产估价的原理,把握房地产估价的实质。     

技术性贸易壁垒中的政府剩余控制权问题研究——对TBT的一个新制度经济学分析框架

本文引入新制度经济学的不完全契约与剩余控制权概念,将TBT以及相关协议看作各国政府签定的一个有关技术性贸易壁垒的不完全契约。由于契约的不完全,从而导致了政府在技术性贸易壁垒问题上的剩余控制权。本文尝试建立起对于技术性贸易壁垒问题的新制度经济学的分析框架,并在此框架下探讨了技术性贸易壁垒层出不穷的制度根源以及政府剩余控制权的结构、特点、表现等。最后,从制度层面上给出了降低技术性贸易壁垒的相关建议。     

新加坡对华投资的现状及对策

在面对21世纪经济全球化的挑战，特别是2001年以来全球经济普遍衰退的情况下，新加坡为寻求新的发展机遇，提出了三大战略，即“高科技战略”、“中国战略”和“扩大腹地战略”。新加坡政府有关部门以及工商界对赴华投资更是跃跃欲试，新一轮的对华投资热潮即将到来。在这样的背景下，有必要对新加坡在华投资的情况进行一下回顾和总结，从而使新加坡赴我国投资在新的基础上取得更快更好的发展。     

浅论影响我国房地产市场的因素及因素的影响

本文主要通过分析影响我国房地产市场继续上扬的因素,包括我国宏观经济将持续保持良好势头、城市化水平的迅速提高、人民币仍处于升值通道中等;以及促使房地产市场回归理性的因素,包括加息、加大保障性住房的供给力度、提高房贷首付、房地产开发及土地储备贷款受到严格管控、开征物业税等;并且具体分析了它们是如何影响市场的,并最终得出结论。     

广西重点实验室管理和运行机制的问题与对策

文章系统地介绍了广西重点实验室的管理模式和运行机制,并针对实验室管理和运行中存在的问题,探讨改革和完善实验室管理和运行机制的对策建议。