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11.
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   
12.
针对突发信号解调中多普勒频偏大的问题,提出了一种改进的连续相位移频键控信号(CPFSK)频率估计方法。首先接收信号平方运算使信号的调制指数加倍,再通过一次离散傅里叶变换(DFT),用搜索信号平方谱谱峰的方法实现突发信号频率估计。仿真实验表明,在低信噪比条件下,该算法的频率估计精度比经典的相位差频率估计算法提高了20%;该算法与广泛用于高动态突发信号的频率插值估计算法相比,同道干扰信道下信干比改善可达4 dB,DFT长度缩短约1/3。  相似文献   
13.
针对多源信号关联难度大、关联准确率低的问题,利用同一目标平台上搭载的多个辐射源信号具有一致的动态变化趋势这一特点,提出一种利用相位差特征的多源信号关联方法。已知阵列形式和侦测点位置,通过对侦收到的多个辐射源信号进行处理,获取相位差信息并累积形成相位差变化趋势;对比提取疑似相似段,根据相似性判决策略进行有效关联。该方法能有效避免不同传感器对位置测量的误差影响,相比传统基于位置信息关联的方法,能有效提升关联准确率。仿真和实测数据分析证明了该方法的有效性,在阵列形式和侦测点位置已知的条件下该方法具有重要工程意义。  相似文献   
14.
Forecasts are a central component of policymaking; the Federal Reserve's forecasts are published in a document called the Greenbook. Previous studies of the Greenbook's inflation forecasts have found them to be rationalizable but asymmetric if considering particular subperiods, for example, before and after the Volcker appointment. In these papers, forecasts are analyzed in isolation, assuming policymakers value them independently. We analyze the Greenbook forecasts in a framework in which the forecast errors for different variables are allowed to interact. We find that allowing the losses to interact makes the unemployment forecasts virtually symmetric, the output forecasts symmetric prior to the Volcker appointment, and the inflation forecasts symmetric after the onset of the Great Moderation.  相似文献   
15.
The monthly data of China's log import from January 2000 to December 2013 are used to estimate the import demand elasticities, with the consideration of possible price endogeneity due to China's large share of the international log market, and structural break caused by global financial crisis in 2008. To address the possible structural break, cointegration tests allowing for a deterministic shift in the level of the variables are employed, and a two-stage estimation with top-down sequential elimination algorithm is performed on the restricted subset VECM. The results demonstrate that there exists a long-run cointegration relationship between China's log import and the explanatory variables. The import elasticities of macroeconomic development and import price are around 0.76 and −0.81, respectively. Other things being equal, the structural break would induce a 29.6% decline in China's log import. All the above parameters are significant at the 1% risk level. Furthermore, the contribution decomposition analysis suggests that China's macroeconomic development plays a dominant role in determining its log import, which implies that China's log import would not increase as quickly as before, given that its economy is shifting into the “New Normal State”. This conjecture is supported by our simulations, which indicate that, by 2020, the growth rate of China's log import will be lower than it has been in the past and the import volume would be approximately 1.1–1.6 times greater compared to imports in 2013.  相似文献   
16.
The relative importance of permanent versus cyclical shocks to GDP has been found to depend on the presence or absence of a single break in mean growth. We estimate unobserved components models conditional on a trend break having occurred in any specified quarter and use the Bayesian model averaging to combine the conditional estimates. We estimate a break occurred around 2006:1. Allowing for a break significantly reduces estimates of trend variance. However, enough spread remains in the posterior distribution to indicate that available data does not definitively settle the question of the relative importance of trend versus cycle.  相似文献   
17.
我国将于2012年通过购买力平价换算GDP参与国际比较项目(ICP),人民币购买力平价在长期内是否成立是我国能否顺利参与这一项目的关键。在中外购买力平价(PPP)实证研究的基础上,选择三变量模型,对1950~2009年间人民币汇率及其中美CPI年度数据进行实证检验。旨在为我国参与ICP提供理论上的支持。  相似文献   
18.
货币政策中介目标是货币政策体系中的重要组成部分,合适的货币中介目标对保持国民经济持续稳定增长具有重要意义。采用基于ARDL模型的协整分析方法,对货币中介目标与中国国民经济增长的关系进行了深入研究,发现通货膨胀率对国民收入的影响幅度最大、货币供应量对国民收入的影响次之,而利率对国民收入的影响相对较小。认为在目前条件下,我国应从过于强调货币供应量指标,转向综合利用多种金融变量来指导货币政策的操作,但在将来市场体系完善后,可考虑采用通货膨胀作为货币政策中介目标。  相似文献   
19.
章针对岩滩水电厂建成投运发电历史数据,全面分析了岩滩水电厂302.5MW(单机容量)发电机组进相运行对机组的负面影响、存在问题及对电能损失情况,为今后妥善解决这类问题提供依据和参考。  相似文献   
20.
移相器是某雷达高功率隔离器的重要组成部分,其结构复杂、尺寸精度高、加工难度大。文章提出通过在生产过程中运用高速切削加工技术、低温真空钎焊技术、三坐标测量技术等相关技术,有效的降低了移相器加工难度,提高了产品质量。  相似文献   
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