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151.
152.
Moussa Kounta 《Journal of Difference Equations and Applications》2013,19(8):1276-1291
We consider the so-called gambler's ruin problem for a discrete-time Markov chain that converges to a Cox–Ingersoll–Ross (CIR) process. Both the probability that the chain will hit a given boundary before the other and the average number of transitions needed to end the game are computed explicitly. Furthermore, we show that the quantities that we obtained tend to the corresponding ones for the CIR process. A real-life application to a problem in hydrology is presented. 相似文献
153.
We investigate the process that different interactions between investors will prompt information to propagate along a differentiated path and construct a financial market model. As information spreads, increasingly investors are attracted to participate in trading, then the “herding effect” is magnified gradually, which will induce the topology of market network to change and the price to fluctuate. Especially, under different initial conditions or parameters, the peak and fat-tail property is produced and the obtained statistic values coincide with empirical results: the power-law exponents between the peak value of return probability distribution and the time scales range from 0.579 to 0.747, and the exponents between the accumulation distribution and the return on the tail are close to 3. Besides, the extent of volatility clustering in our produced price series is close to that of S&P 500 and locates between NASDAQ and HSI. All the results obtained here indicate that the continuous variation of the “herding effect” resulting from information propagation among interacting investors may be the origin of stylized facts of price fluctuations. 相似文献
154.
会计师事务所的独立性在世界范围内遭到了不同程度的质疑。本文搜集了1998-2009年间受到证监会处罚并经三大权威报纸披露的31家舞弊公司的信息,将其作为舞弊研究样本,另外整理了同行业同年度财务状况良好的31家非舞弊公司的信息,将其作为对照样本。通过归纳我国上市公司财务舞弊的具体特征,本文选取了与企业经营有关的相关财务指标和公司治理指标作为解释变量,采用逐步向前的多元逻辑回归法构建财务舞弊侦测模型,经验证,该模型侦测准确度为73.8%。 相似文献
155.
以传统CPPI投资策略的分析框架为基础,在风险资产为连续价格波动的条件下,构建离散投资决策时点的CPPI投资策略。引入模糊决策的分析方法度量投资决策者的心理预期,将传统CPPI投资策略中的投资乘数修正为随机模糊投资乘数,采用马尔科夫链蒙特卡洛模拟风险资产未来市场价格,利用模糊隶属函数描述投资决策者对未来市场运行状况预期的不确定性,保证即使投资决策者预期不精确的条件下,也能保证离散CPPI投资策略获得相对稳定的投资效果。利用中国证券市场上的真实数据进行实证检验,认为:随机模糊投资乘数最大限度地涵盖了投资决策者主观预测的不确定性;基于随机模糊投资乘数的离散CPPI投资策略在不同的市场运行状况中,较传统的CPPI投资策略更具投资的灵活性,可以在保证投资保险的前提下,追求较高的投资收益。 相似文献
156.
157.
通过构建鄱阳湖地区城市金融生态环境评价指标体系,运用熵权法和灰色综合评价法对2007年、2008年和2009年鄱阳湖地区6个地级市(南昌、景德镇、九江、新余、鹰潭、抚州)的金融生态环境现状进行了综合评价。结果表明:鄱阳湖地区城市金融生态环境发展的非均衡性比较严重,南昌和新余2个重点城市金融生态环境表现较好,其余城市的金融生态环境发展水平普遍不高。 相似文献
158.
MA Shi-Hao 《理论物理通讯》2009,51(2):358-362
A systematic analysis of Shanghai and Japan stock indices for the period of Jan. 1984 to Dec. 2005 is performed. After stationarity is verified by ADF (Augmented Dickey-Fuller) test, the power spectrum of the data exhibits a power law decay as a whole characterized by 1/f^β processes with possible long range correlations. Subsequently, by using the method of detrended fluctuation analysis (DFA) of the general volatility in the stock markets, we find that the long-range correlations are occurred among the return series and the crossover phenomena exhibit in the results obviously.Further, Shanghai stock market shows long-range correlations in short time scale and shows short-range correlations in long time scale. Whereas, for Japan stock market, the data behaves oppositely absolutely. Last, we compare the varying of scale exponent in large volatility between two stock markets. All results obtained may indicate the possibility of characteristic of multifractal scaling behavior of the financial markets. 相似文献
159.
J. B. Satinover D. Sornette 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,67(3):357-367
In the Minority, Majority and Dollar Games (MG, MAJG, $G) agents compete for rewards, acting in accord with the previously
best-performing of their strategies. Different aspects/kinds of real-world markets are modelled by these games. In the MG,
agents compete for scarce resources; in the MAJG agents imitate the group to exploit a trend; in the $G agents attempt to
predict and benefit both from trends and changes in the direction of a market. It has been previously shown that in the MG
for a reasonable number of preliminary time steps preceding equilibrium (Time Horizon MG, THMG), agents’ attempt to optimize
their gains by active strategy selection is “illusory”: the hypothetical gains of their strategies is greater on average than
agents’ actual average gains. Furthermore, if a small proportion of agents deliberately choose and act in accord with their
seemingly worst performing strategy, these outperform all other agents on average, and even attain mean positive gain, otherwise
rare for agents in the MG. This latter phenomenon raises the question as to how well the optimization procedure works in the
THMAJG and TH$G. We demonstrate that the illusion of control is absent in THMAJG and TH$G. This provides further clarification
of the kinds of situations subject to genuine control, and those not, in set-ups a priori defined to emphasize the importance
of optimization. 相似文献
160.
M. B. Gordon J. R. Iglesias V. Semeshenko J. P. Nadal 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,68(1):133-144
Crime is an economically relevant activity. It may represent a mechanism of wealth distribution but also a social and economic
burden because of the interference with regular legal activities and the cost of the law enforcement system. Sometimes it
may be less costly for the society to allow for some level of criminality. However, a drawback of such a policy is that it
may lead to a high increase of criminal activity, that may become hard to reduce later on. Here we investigate the level of
law enforcement required to keep crime within acceptable limits. A sharp phase transition is observed as a function of the
probability of punishment. We also analyze other consequences of criminality as the growth of the economy, the inequality
in the wealth distribution (the Gini coefficient) and other relevant quantities under different scenarios of criminal activity
and probabilities of apprehension. 相似文献