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961.
The objective of this paper is to evaluate the impact of information demand and supply on stock market trading volume. Few studies have demonstrated the role of Google search data in analyzing trading volume activity. In this study, we employ a proxy for information demand which is derived from weekly internet search volume. The latest is from Google Trends database, for 25 of the largest stocks traded on CAC40 index, between April 2007 and March 2014. We use news headlines as a proxy for information supply. We use Garch model to analyze and predict trading volume.The empirical results present new evidences. First, information supply has an impact on trading volume but information demand's impact is much more important. Secondly, by applying MCA to results found, it could be concluded that the impact of public information on transaction volume is conditioned by two elements: the firm and market news disclosure and the second element relates to the characteristics of the market participants, more precisely their news interpretations and their risk aversion. Thirdly, we used Chow structural break test to verify the stability of our model. We found that for securities with structural changes, information demand is the responsible variable of the change in our model. Finally, we found that information variables have a predictive power on transaction volume.This paper contributes to existing literature by incorporating open source internet-based data into the analysis and prediction of transaction volume. Using internet information about the stock market, which has appeared recently as an interesting research for financial empiricists, computer scientists and practitioners, will have a very important utility because quantifying demand and supply of information becomes possible.  相似文献   
962.
[目的]农业可持续发展的研究首先面临的一个问题是如何对其进行有效评价,农业可持续发展评价一般采用多指标评价法,然而过多的指标给实际操作带来很多困难。文章从可持续发展评价理论创新和方法创新的需求出发,寻求建立一个简便易行的综合性指标——农业可持续发展指数(ASDI),以提高农业可持续发展评价的有效应和准确性。[方法]该文基于能量投入产出方法,利用Logistic曲线构建了ASDI,并以贵州省印江县为实证研究案例,对其农业生态的可持续性行进行评价分析。[结果]通过研究发现印江县的ASDI具有很大波动性,由于2002~2007年农业投入增加,印江县的ASDI呈现下降趋势,其中2007年因为投入过多而出现了负效应指数。[结论](1)利用一个简单的综合指标来评价农业可持续发展在理论和实践上是可行的;(2)ASDI作为农业可持续发展的研究,或将为生态安全预警提供了一个可供参考的指标。  相似文献   
963.
The reasons for people’s food choices are complex and result from the interplay of several influences throughout various contexts. Although research has found that various factors influence people’s food choices, investigators have not considered the diverse elements affecting the methods or the procedures that people employ for selecting healthy foods in the context of full-service restaurants. Therefore, the current study was conducted to better comprehend family or casual dining consumers’ choices in relation to healthy eating behaviors. This qualitative study purposefully sampled three focus group interviews with three different types of participants (mature, nonmature, and chef/manager) to identify important factors that can encourage people to buy or eat healthy foods when dining at full-service restaurants. Content analysis of 16 interviews revealed three levels of healthy food choice factors that affect customers who want to enjoy healthy foods in full-service restaurants.  相似文献   
964.
The bureaucratic and impersonal nature of public management can fertilize workplace bullying and risks for psychological health and safety. Psychological safety climate (PSC) is an important indicator to reduce psychological hazards. Yet, there have been few studies conducted to examine the existence of PSC in the public sector in non-Western economies. This study examined the implementation of PSC and its effects on 274 employees from six branches of a Vietnamese public sector organization. The results suggest that senior management in organizations should consider positive work conditions and an effective system of policies, procedures, and practices for the prevention of psychosocial hazards.  相似文献   
965.
This paper presents an application of the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) approach to the analysis of rural land uses. Using secondary data on farming systems in Laos, we illustrate how the concept of metabolic pattern can be used to establish links between the various indicators of performance of rural systems. To this purpose, we characterize the socioeconomic activities in rural Laos by a series of quantitative indicators defined across: (i) different hierarchical levels of organization described at different scales (i.e. households, rural villages, administrative regions and the whole country) and (ii) different dimensions of analysis, including economic, agronomic, social, biophysical, and ecological analysis. The MuSIASEM approach simultaneously employs two non-equivalent criteria for quantification. The observed rural system is described in terms of an integrated set of flow elements (money, food, energy, water, fertilizer and other materials), which are mapped against two distinct fund elements: (i) a multi-level matrix of human activity (flows being expressed in terms of intensity per hour) and (ii) a multi-level matrix of land uses (flows being expressed as density per hectare). Our case study shows that in this way it is possible to move across different hierarchical levels, scales and dimensions, to arrive at an integrated representation of the metabolic pattern of farming systems.  相似文献   
966.
城市公园是城市的重要组成部分,是调节城市生态环境的重要场所,也是城市居民休憩、娱乐和活动的重要开敞空间,因此分析城市公园设施的利用情况以及利用者的行为特性,对于城市公园的建设和管理有十分重要的意义。以上海市中山公园为例,通过对该公园利用情况的分析,了解到公园的利用者大多数为青年人和老年人,且利用者范围广,利用频率高,滞留时间也较长。同时运用数量化Ⅲ类和聚类分析方法,把城市公园利用者的行为特性分为郊游式利用型、日常利用型、临时利用型、约会利用型、幼儿同行利用型、健康注重型及非日常团体活动型7大类,分析了各类利用者行为特性的特点,为今后政府部门对公园的建设和管理提供一些新的思路。  相似文献   
967.
以国家会议中心各部门的一线服务人员及其所服务的客户作为主要调查对象,259份有效问卷作为样本,利用SPSS20.0对调查结果进行典型相关分析,探析了员工授权知觉与服务质量的关系。结果表明:组织员工授权知觉和员工服务质量之间存在正相关关系,员工对自己工作能力的信心强度和对自己是否拥有工作自主权与独立权的感知程度更能有效的影响到客户对员工服务质量的评价,在提高员工授权知觉的情况下,员工的服务质量会得到提高,并凸显在服务的效率和可靠性这两方面。对一线服务员工进行适当的放权,使其授权知觉水平提高,有利于增强员工自信心,树立员工的责任感和价值感,提高员工服务工作的效率及可信赖性。  相似文献   
968.
为科学准确地反映2014年我国入境旅游业发展的总体状况,国家旅游局统一部署、省旅游局组织实施了"入境游客花费情况抽样调查"。本次调查是纳入《旅游统计调查制度》的国家调查项目,问卷按6种语种(即中、英、法、日、韩、俄)印刷,课题组完成了2014年武汉市入境游客抽样调查与分析报告。  相似文献   
969.
This article studies a container drayage problem with flexible orders defined by using requiring and releasing attributes as a unified formulation of various order types. A determined-activities-on-vertex (DAOV) graph introduces a temporary vertex set to formulate different truck statuses. The problem is formulated as a mixed-integer nonlinear programming model based on the DAOV graph. Four strategies including a window partition based (WPB) strategy are presented and evaluated extensively to solve the problem. Results indicate that the WPB method could solve the problem effectively and efficiently. Furthermore, this method is robust considering the operating time biases compared to other algorithms.  相似文献   
970.
徐梦辉 《时代经贸》2014,(6):179-179
在经济全球化大环境下,企业具有更加多样化的会计信息,也就更需要能全面反映企业业绩的财务分析体系。多年来传统杜邦分析法虽因能系统、全面、直观地反映企业财务状况,提高对财务报表的分析效率,提升经营管理能力而得到企业的广泛应用,但它本身存在着诸多缺陷。针对其局限性,本文引入可持续增长率来改进传统的杜邦分析体系以更加符合现代企业的要求。  相似文献   
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