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排序方式: 共有390条查询结果,搜索用时 15 毫秒
1.
We analyze the relationship of retail investor sentiment and the German stock market by introducing four distinct investor pessimism indices (IPIs) based on selected aggregate Google search queries. We assess the predictive power of weekly changes in sentiment captured by the IPIs for contemporaneous and future DAX returns, volatility and trading volume. The indices are found to have individually varying, but overall remarkably high explanatory power. An increase in retail investor pessimism is accompanied by decreasing contemporaneous market returns and an increase in volatility and trading volume. Future returns tend to increase while future volatility and trading volume decrease. The outcome is in line with the conjecture of correction effects. Overall, the results are well in line with modern investor sentiment theory.  相似文献   
2.
工作流管理系统的结构与应用   总被引:1,自引:0,他引:1  
本文介绍了用于企业业务流程管理的工作流的结构和应用 ,详细地说明了各个阶段的功能实现以及工作流引擎等 ,最后讨论了工作流在实际实现中的各种应用。  相似文献   
3.
应用灰关联理论对发动机的故障进行诊断。灰关联分析属非函数型的序列模式,能有效处理杂散数据。通过建立工程机械发动机系统故障树,运用灰关联分析对关联度进行计算及排序,给出各种故障模式发生的可能性排序,从而为处理故障、控制故障的发生以及改进系统的可靠性提供理论依据。  相似文献   
4.
伴随Internet爆炸性的发展,以及网上信息资源的快速增长,网络搜索引擎便应运而生了。而如今越来越多的研究者依赖于搜索引擎获得信息,人们的工作、学习、生活与网络搜索引擎已密不可分,把搜索比喻成是一种生活方式已毫不为过。所以,认识和研究网络搜索引擎有着非常重要的现实意义。  相似文献   
5.
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   
6.
为了解决航空发动机双通道电子控制器(EEC)两个通道均发生故障时如何评估通道健康度,从而选择主控通道的问题,论文提出了基于逆模型计算发动机推力敏感度的方法,量化不同信号故障对发动机推力的影响程度,依据推力敏感度来评估双通道健康度,协助主控通道选择,最终提高系统的安全性。  相似文献   
7.
在减轻大气污染对策的问题里,严格治理柴油机冒烟具有重要意义。  相似文献   
8.
We utilize the Internet search data from Google Trends to provide short-term forecasts for the inflow of Japanese tourists to South Korea. We construct the Google variable in a systematic way by combining keywords to minimize mean squared or mean absolute forecasting errors. We augment the Google variable to the standard time-series forecasting models and compare their forecasting accuracies. We find that Google-augmented models perform much better than the standard time-series models in terms of short-term forecasting accuracy. In particular, Google models show better out-of-sample forecasting performance than in-sample forecasting.  相似文献   
9.
Genericide refers to situations where brands lose their legal protections due to the fact that their original name has become the generic term for a new category of products in the market that the brand first helped to create. Despite notorious instances of brands falling prey to this curse, marketing specialists—unlike lawyers—generally do not consider that the widespread use of a brand name represents any real danger and instead view it as a sign of brand strength. Herein, we take a new look at this debate, using a case study of Google to re-investigate the phenomenon of genericide. The article also offers managerial guidance on the most effective ways of developing genericization and avoiding genericide. It concludes by pointing out the need for brand managers to precisely differentiate between different types of brands and markets when deciding whether they should protect themselves from the risk of genericide or else encourage the genericization of their brand.  相似文献   
10.
相比较传统地形图,Google Earth具有三维效果,图像具有内容丰富真实、更新速度快、比例尺大小切换便捷等优点,对于油田管线及电力线路的勘察设计工作具有很大的帮助。本文结合油田生产实际,对该软件运用于管线及电力线路的勘察设计工作进行了介绍说明。  相似文献   
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