作物面积空间抽样研究进展

粮食作物面积的准确及时估计对国家粮食政策和宏观经济计划的制订具有重要意义。现有国内外作物面积的统计调查主要使用空间抽样方法进行。该研究从作物面积空间抽样方法、抽样基础单元(样方尺寸)优化及样本空间布局的合理布设3个方面,对国内外相关研究进展进行了总结和归纳。在此基础上,总结了现有作物面积空间抽样研究存在的问题和不足,指出了今后作物面积空间抽样研究的方向和重点。     

日韩贸易摩擦的原因、影响及趋势分析

日本对出口韩国的生产半导体零部件的3种核心原材料采取管制措施,其根本目的在于掌握半导体乃至高技术领域的主导权。出口管制实施后,部分日本企业试图通过拓展其他国家市场来弥补因对韩出口管制造成的损失,也有些企业计划在海外设厂以便避开政府管制向韩国供应原材料。出口管制还导致日本产品在韩遭到抵制、韩国赴日游客锐减等。韩国通过半导体核心部件国产化、进口来源地多元化等对策,在一定程度上减少了贸易制裁对半导体行业的负面影响,使日本被迫放宽出口管制。由于日韩处于半导体全球价值链分工不同环节中,存在紧密的"一荣俱荣,一损俱损"的依存关系,因此,日韩贸易摩擦的缓和存在内在必然性。另外,RCEP签署以及中日韩自贸区谈判等外部因素会进一步促进日韩贸易关系改善。     

Multiple switching behaviour in different display formats of multiple price lists

A common approach to elicit risk attitude is the multiple price list with a series of binary choices. However, a frequently observed problem when using multiple price lists is that participants switch more than once from the safer to the riskier option, thus exhibiting multiple switching behaviour. The present study analyses whether the visualization of different multiple price lists reduce multiple switching behaviour. Therefore, we conduct two types of multiple price lists in two different display formats. Participants are randomly assigned into a textual or a visual group and carry out both multiple price lists in the corresponding display format. Our results reveal that different types of multiple price lists lead to differences in the extent of multiple switching behaviour. Moreover, we show that the visualization of a multiple price list can be an instrument to greatly reduce multiple switching behaviour.     

Intermediate Choice Lists: How Product Attributes Influence Purchase Likelihood in a Self-Imposed Delay

Many online retailers enable consumers to postpone a purchase decision by placing a desired item onto an intermediate choice list, such as a wish list or saved-for-later list. This research demonstrates that using a list in this way decreases purchase intent for the wait-listed products, relative to the same choice made without the option to delay the decision. The findings of five experiments show that purchase likelihood is affected by a shift in the importance, or weight, of product attributes. Specifically, the attributes that are weighted more heavily in the decision to place an item on an intermediate choice list are then weighted less heavily in the decision to purchase an item from that list. This shift in attribute weighting suggests that consumers may switch from more noncompensatory to more compensatory decision-making between the initial decision to use an intermediate choice list, and the later decision of whether to purchase the item from the list. This process tends to diminish the importance of the attractive attributes that encouraged consumers to put these items on lists in the first place. These findings have implications for retailers who wish to understand the risks and benefits of wish lists and related tools, and for consumers who desire to reduce impulsive purchases.     

极化码的参数捷变技术及性能仿真

极化码是首个能够从理论上证明接近信道容量的纠错码，于2016年11月和低密度奇偶校验码一并作为第5代移动通信的标准。针对极化码特有的蝶形结构采用Trellis对其进行了重新描述，详细分析了串行抵消列表译码算法。同时，基于密度进化理论给出了极化码的码参数捷变技术，能够在不改变编译码器硬件结构与程序的情况下实时、快速地改变编译码参数。仿真结果表明，在编码参数近似相同的情况下极化码的性能要优于低密度奇偶校验码。     

Is UNESCO recognition effective in fostering tourism? A comment on Yang,Lin and Han

The purpose of this response to the original work by Yang, Lin and Han (Tourism Management, 2009), is to continue discussion of the impacts created by the formal accreditation of sites through the process of UNESCO recognition. In the particular case described by Yang, Lin and Han, alternative interpretations of the results may be offered. Additional evidence is also provided from instances in Italy and overall it appears that econometric analysis questions the degree to which UNESCO accreditation generates the economic returns from tourism that may have prompted the original applications.     

基本药物制度对中国医药行业未来发展的影响初探

2009年8月18日,国务院发布了《关于建立国家基本药物制度的实施意见》、《国家基本药物目录管理办法（暂行）》和《国家基本药物目录（基层医疗卫生机构配备使用部分）》（2009版）,标志着中国建立国家基本药物制度工作的正式实施,由此将对中国医药行业的发展产生深远影响：确保了医药行业整体的稳定发展,改变竞争格局,下调价格将影响部分企业申报进入基本药物目录的品种,进入基本药物目录的独家品种的医药生产企业将充分受益,加速国内仿制药企业抢占市场空间。中国医药企业在基本药物制度下必须有新的发展思路。     

我国上市公司管理层收购绩效研究

本文运用统计学的因子分析法,对我国2001-2002年17家实施了MBO的上市公司经营绩效进行了实证研究,结果表明:上市公司的经营业绩在MBO当年和后一年有所上升,但在MBO后两年却出现了一定程度的下滑。在目前,由于我国MBO运行的市场环境和制度环境尚不成熟和不完善,上市公司MBO还须慎行,应采取切实可行的措施规范上市公司MBO,以使上市公司MBO后的经营绩效能稳步提升。     

Topics and trends in finance research: What is published,who publishes it and what gets cited?

In this study we provide a detailed examination of the subject matter of finance research and its institutional features as it has evolved over the past two decades. Drawing on novel approaches from data science, we examine the content of more than 30,000 published papers. Overall, we find a striking lack of diversity in the topics investigated and the methodological approaches used. Almost all finance research is conducted using techniques from economics and mathematics, with virtually no use made of qualitative methods or interdisciplinary approaches. Looking at the developments of the discipline over time, we document an increase in the volume of corporate finance research and a variation in the topics covered following the financial crisis, although these changes appear to be reactive and trivial rather than paradigm shifts. We also provide a cartography of research in finance and its citation-based impact by the location of authors. Leading finance research is concentrated in elite US institutions, and has a disproportionately strong citation-based impact. Compared with other business and management sub-fields, citations in finance are heavily skewed towards the top journals as the latter generate almost twice as much impact as the lower rated outlets.     

工程量清单模式下的电力工程招标与投标管理

近年来,我国社会经济已经进入了高速发展的时期,电力企业作为我国国民经济的重要组成部分,对我国经济的快速增长具有不可或缺的意义。传统的招投标管理模式已经难以满足当今新时期社会的发展,必须对其模式进行创新与完善。工程量清单模式是一种全新的招投标管理模式,因其具有诸多优点在电力工程招投标管理中得到了广泛的应用。