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991.
Forecasts of values at risk (VaRs) are made for volatility indices such as the VIX for the US S&P 500 index, the VKOSPI for the KOSPI (Korea Stock Price Index) and the OVX (oil volatility index) for crude oil funds, which is the first in the literature. In the forecasts, dominant features of the volatility indices are addressed: long memory, conditional heteroscedasticity, asymmetry and fat-tails. An out-of-sample comparison of the VaR forecasts is made in terms of violation probabilities, showing better performance of the proposed method than several competing methods which consider the features differently from ours. The proposed method is composed of heterogeneous autoregressive model for the mean, GARCH model for the volatility and skew-t distribution for the error.  相似文献   
992.
Due to the advantages of being able to function under harsh environmental conditions and serving as a distributed condition information source in a networked monitoring system, the fibre Bragg grating (FBG) sensor network has attracted considerable attention for equipment online condition monitoring. To provide an overall conditional view of the mechanical equipment operation, a networked service-oriented condition monitoring framework based on FBG sensing is proposed, together with an intelligent matching method for supporting monitoring service management. In the novel framework, three classes of progressive service matching approaches, including service-chain knowledge database service matching, multi-objective constrained service matching and workflow-driven human-interactive service matching, are developed and integrated with an enhanced particle swarm optimisation (PSO) algorithm as well as a workflow-driven mechanism. Moreover, the manufacturing domain ontology, FBG sensor network structure and monitoring object are considered to facilitate the automatic matching of condition monitoring services to overcome the limitations of traditional service processing methods. The experimental results demonstrate that FBG monitoring services can be selected intelligently, and the developed condition monitoring system can be re-built rapidly as new equipment joins the framework. The effectiveness of the service matching method is also verified by implementing a prototype system together with its performance analysis.  相似文献   
993.
In this paper, we introduce a new Bayesian approach to explain some market anomalies during financial crises and subsequent recovery. We assume that the earnings shock of an asset follows a random walk model with and without drift to incorporate the impact of financial crises. We further assume the earning shock follows an exponential family distribution to accommodate symmetric as well as asymmetric information. By using this model setting, we develop some properties on the expected earnings shock and its volatility, and establish properties of investor behavior on the stock price and its volatility during financial crises and the subsequent recovery. Thereafter, we develop properties to explain excess volatility, short-term underreaction, long-term overreaction, and their magnitude effects during financial crises and the subsequent recovery. We also explain why behavioral finance theory could be used to explain many of the asset pricing anomalies, but traditional asset pricing models cannot achieve this aim.  相似文献   
994.
These three books take different approaches to analysing the transformative potential of the Landless Workers Movement (MST) in Brazil. Vergara‐Camus' book also examines the Zapatista National Liberation Army (EZLN). Carter solicited essays from numerous specialists and sees his book as contributing to existing efforts to overcome inequality. Mészáros emphasizes the influence of power relations on the law, determining that it takes an organized pressure group such as the MST to ensure that authorities implement policies that challenge the status quo. Vergara‐Camus' grassroots approach, which involved periods of living with peasant families, concludes that the MST's strategies for building alternative, autonomous rural communities is more realistic – more universalistic – than that of the Zapatistas, whose military tactics tend to reinforce the group's isolation in the forests of Mexico's southernmost state. The review evaluates these arguments, the authors and their evidence from the perspective of a researcher experienced with the objects studied.  相似文献   
995.
This study investigates the impact of low-cost carriers (LCCs) on Saudi Arabia's tourism demand. It also provides an understanding of the relationship between air transport development and tourism development in the Gulf region. The Box–Jenkins SARIMA-X models were employed to model and forecast international tourist arrivals to Saudi Arabia, using monthly international tourist arrivals to Saudi Arabia from July 2010 to December 2015. The forecasting models were significantly accurate, with lower values of MAPE, MAP, and RMSE. The findings suggest that an increase in airline capacity, religious travel, and airline competition are associated with the increasing international tourist arrivals to Saudi Arabia. This also indicates that there is a positive relationship between air transport development and tourism development. Further aviation liberalisation in the Gulf region is discussed to give opportunities for the region's LCCs to increase their share of the increasing air travel demand, thereby enhancing tourism development.  相似文献   
996.
The study used quarterly panel data of 6 years from 2010 to 2015 of all companies listed on both Vietnamese stock markets including the Ho Chi Minh City Stock Exchange and Ha Noi Stock Exchange, and on three leading industries consisting of insurance-banking, foodstuff, and real estate to explore the relationship among four key financial ratios and stock trading volume. Two models, fixed effects model (FEM) and random effects model (REM), with robust standard errors, were applied for this study. The key findings showed that earnings before tax on sales, debt on owner’s equity, and owner’s equity on total assets significantly influenced trading volume.  相似文献   
997.
王薇 《价值工程》2014,(32):224-225
本文深刻分析了当前我国企业内部审计发展中存在的主要问题,提出了推进我国内部审计发展的具体措施。  相似文献   
998.
This study considers risky investment projects under adverse selection and examines optimal penalties for erroneous auditing reports to maximize social welfare. These penalties give firms an incentive to choose accounting policies that maximize social welfare. We characterize the optimal penalties such that efficient firms choose an aggressive accounting policy and inefficient firms choose a conservative accounting policy.  相似文献   
999.
采用离子球模型研究了强耦合氢等离子体中杂质Be3+的原子结构和光谱性质随离子球大小的变化规律.结果表明,强耦合等离子体的屏蔽效应对其中的原子结构和光谱影响很大,而且不同模型给出的结果有很大的差别;在离子球模型下,类氢的轨道电离能随着屏蔽效应的增强而单调减小,轨道的简并度解除,但是随着屏蔽效应的增强,轨道将二次简并,轨道能级关于角动量发生发转;不同主量子数n两能级之间辐射的光谱随着屏蔽效应的增强先红移而后蓝移,在非相对论情况下,屏蔽效应引起同n轨道能级劈裂,辐射出新的光谱,该光谱随着等离子体效应的增强先蓝移后红移,经过再次简并后继续蓝移,直到不再辐射出光谱为止;轨道之间的重叠积分由于等离子体屏蔽效应先减小而后增大,从而振子强度随着等离子体屏蔽效应的增强先减小而后增大.目前的计算数据与可查的数据非常符合.  相似文献   
1000.
利用广西1978—2012年地区生产总值、银行贷款和银行存款的时间序列数据,建立了三者之间动态关系的向量自回归模型(VAR)。研究结果显示:银行贷款和银行存款对地区经济增长有促进作用,并且银行贷款的影响大于银行存款的影响;在10%的显著水平上,地区生产总值与银行贷款构成双向Granger因果关系;在5%的显著水平上,银行存款与地区生产总值之间只存在单向Granger因果关系。据此,提出了广西金融改革发展的政策建议。  相似文献   
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