对我国开放式基金风险的实证研究——基于GARCH模型的VaR方法

从我国开放式基金收益率序列的分布、波动性和杠杆效应三方面考虑,在正态分布、t分布和GED分布的假设下,-建立了估计基金风险的VaR—GARCH、VaR—EGARCH模型,选择合适的模型对各只基金及不同类型基金的VaR值进行估计,并应用Kupiec方法对VaR模型的准确性进行了返回检验。结果显示,基于GED分布的GARCH模型计算的VaR值比基于t分布的GARCH模型计算的VaR值更真实地反映了基金的风险,不同投资类型和投资风格的基金的风险也不尽相同。     

基于GARCH模型的VaR方法对我国开放式基金风险的分析

本文从我国开放式基金收益率序列的分布与波动性两方面建立了一个估计基金风险的VaR-GARCH模型,在正态分布和能够刻画收益率的尖峰厚尾特征的t分布GED分布三种不同的分布假设下,对基金的VaR值进行估计,并应用Kupiec失败频率检验方法对VaR模型的准确性进行了返回检验。结果显示,基于GED分布的GARCH模型计算的VaR值比基于正态分布和t分布GARCH模型计算的VaR值更真实地反映了基金的风险。     

我国商业银行市场利率风险的VaR度量实证研究

运用GARCH族模型和分位数回归的方法对我国商业银行利率风险进行VaR度量,从而测算我国商业银行的利率风险,运用上海银行间同业拆借市场（Shibor）的隔夜拆借利率数据进行研究。通过GARCH族模型的选取可以得出正态分布和T分布并不适合我国商业银行间同业拆借市场,本文选取广义误差分布（GED）对数据进行GARCH建模并测算其VaR,同时本文运用了分位数回归的方法对VaR进行测算,从结果证明分位数回归方法更适合VaR的度量。     

上证综指收益波动性及VaR度量研究

基于对上证综指日回报序列分布分别作正态分布、t分布和广义误差分布(GED)的假设基础上,采用(E)GARCH模型和方差-协方差法,度量了上海股票市场的潜在风险和波动性。在验证了三个模型对VaR估计的有效性之后,得出AR(1)-EGARCH(1,1)-M-GED模型对上海股票市场的拟合最优,并得出了有效的VaR估值。     

开放式基金风险比较的实证研究

开放式基金风险应该根据其类别和经营管理风格等因素进行划分。根据样本数据的特定性质,通过采用GARCH模型,对开放式基金的基金收益波动进行模拟,分别计算了代表性开放式基金的VaR值,并引入RAROC方法比较了开放式基金的风险。结论表明,投资者和管理者应该结合开放式基金的管理风格进行横向比较,使用绝对VaR和RAROC指标综合考察开放式基金的风险和收益。     

GARCH模型在计算上海股市风险价值中的应用研究

本文主要讨论VaR模型中有关波动率的估计方法.通过研究上证综合指数收益波动特征,发现其收益率服从高阶ARCH过程.然后分别采用GARCH(5,4)模型和RiskMetrics标准法预测上证综合指数收益的VaR值.返回式检验表明,GARCH模型比RiskMetrics标准法能更准确地反映我国上海股市的风险.     

基于CVaR的我国银行间债券回购市场利率风险度量研究

在银行间债券回购市场利率基本特征分析基础上,利用我国银行间债券回购开始日1997年6月15日至2008年4月20日全部质押式回购每周加权平均利率进行实证研究,建立了基于ARMA-GARCH模型族的利率风险CVaR测度模型。结果表明我国银行间债券回购市场中存在杠杆效应;回购利率分布对CVaR计算结果影响较大,GED分布较正态分布和t分布能更好刻画我国银行间回购利率序列的分布状况。EGARCH模型计算得到的CVaR值要优于GARCH和TARCH模型得到的结果。     

基于面板GARCH模型的汇率风险联动VaR测算

为弥补现有VaR测算模型在同时测算多汇率风险因子VaR值过程中的不足,笔者将面板CARCH模型应用于汇率风险的VaR测算中,通过与一元GARCH模型、多元GARCH模型中的BEKK模型和DCC模型相对比,发现其联动VaR测算的结果优于后三种模型.基于残差项正态分布假设下的面板GARCH模型能够较好地捕获汇率的波动,其运用能提高VaR测算的精度,增强金融机构或企业的汇率风险管理水平.     

基于GARCH模型的VaR方法的实证分析——以开放式基金为研究对象

从我国开放式基金收益率序列的分布、波动性和杠杆效应三方面考虑,在正态分布、t分布和GED分布的假设下,建立了估计基金风险的VaR-GARCH、VaR-EGAKCH模型.选择合适的模型对各只基金及不同类型基金的VaR值进行估计,最好根据结果得出相应的结论.     

基于Archimedean Copula-GARCH模型的国际原油价格风险度量

本文对国际原油市场价格风险VaR的度量方法进行研究,选择了三种主要的ArchimedeanCopula函数描述随机变量之间的相关关系,运用GARCH对边际分布建模,使用Monte Carlo方法分别计算三个模型下的VaR,并通过回测检验对模型进行检验和比较,结果显示Clayton Copula-GARCH模型估计效果较好.     

基于GJR—ALaplace方法的开放式基金风险研究

根据我国开放式基金收益率序列的尖峰、厚尾、有偏和波动时变的特征,引入非对gg,Laplace分布对收益率序列进行刻画和拟合。构建度量基金风险的动态GJR—Asymmetric～Laplace模型,在非对称Laplace分布、Laplace分布和正态分布三种分布假设下测算VaR,并做返回检验。选取12只开放式基金在2007．01．04～2009．12．31期间的日累计净值数据做实证研究。实证表明：除了基金大成债券外,其余11只基金显著通过假设,符合非对称Laplace分布,相rELaplace分布和正态分布来说,非对称Laplace分布能更好地拟合基金收益率序列。正态分布假设下风险度量值通过检验的基金数显著少于Laplace分布假设,而Laplace分布下通过检验的基金数亦少于非对称Laplace分布,可知非对称hplace分布假设下得出的基金动态风险值更为有效。     

大宗农产品价格风险评估——基于小波神经网络-Bootstrap方法的实证研究

构建了一个将小波神经网络与Bootstrap抽样相结合的价格风险评估模型。采用国际通用的VaR(在险价值)风险指标评估了国内小麦、水稻、玉米、大豆和棉花5种主要大宗农产品现货价格的风险水平,仿真研究了以上大宗农产品价格下跌风险和价格上涨风险的分布特征。结果表明:按价格风险水平由高到低对5种主要大宗农产品进行排序依次为棉花、大豆、玉米、小麦和水稻;从风险均值来看,我国大宗农产品价格特别是粮食价格的风险处于较低水平;从风险的经验分布来看,除大豆外,其他大宗农产品(特别是小麦、水稻和玉米)的涨价风险高于跌价风险;5种农产品的价格均存在偏度风险和峰度风险。     

Markets liquidity risk under extremal dependence: Analysis with VaRs methods

Value-at-Risk (VaR) is a widely used tool for assessing financial market risk. In practice, the estimation of liquidity extreme risk by VaR generally uses models assuming independence of bid–ask spreads. However, bid–ask spreads tend to occur in clusters with time dependency, particularly during crisis period. Our paper attempts to fill this gap by studying the impact of negligence of dependency in liquidity extreme risk assessment of Tunisian stock market. The main methods which take into account returns dependency to assess market risk is Time series–Extreme Value Theory combination. Therefore we compare VaRs estimated under independency (Variance–Covariance Approach, Historical Simulation and the VaR adjusted to extreme values) relatively to the VaR when dependence is considered. The efficiency of those methods was tested and compared using the backtesting tests. The results confirm the adequacy of the recent extensions of liquidity risk in the VaR estimation. Therefore, we prove a performance improvement of VaR estimates under the assumption of dependency across a significant reduction of the estimation error, particularly with AR (1)-GARCH (1,1)-GPD model.     

Risk assessment of oil price from static and dynamic modelling approaches

The price gap between West Texas Intermediate (WTI) and Brent crude oil markets has been completely changed in the past several years. The price of WTI was always a little larger than that of Brent for a long time. However, the price of WTI has been surpassed by that of Brent since 2011. The new market circumstances and volatility of oil price require a comprehensive re-estimation of risk. Therefore, this study aims to explore an integrated approach to assess the price risk in the two crude oil markets through the value at risk (VaR) model. The VaR is estimated by the extreme value theory (EVT) and GARCH model on the basis of generalized error distribution (GED). The results show that EVT is a powerful approach to capture the risk in the oil markets. On the contrary, the traditional variance–covariance (VC) and Monte Carlo (MC) approaches tend to overestimate risk when the confidence level is 95%, but underestimate risk at the confidence level of 99%. The VaR of WTI returns is larger than that of Brent returns at identical confidence levels. Moreover, the GED-GARCH model can estimate the downside dynamic VaR accurately for WTI and Brent oil returns.     

Tail risk in emerging markets of Southeastern Europe

This article examines the left-tail behaviour of returns on stocks in Southeastern Europe (SEE). We apply conditional extreme value theory (EVT) approach on daily returns of six stock market indices from SEE between 2004 and 2013. Predictive performance of value-at-risk (VaR) and expected shortfall (ES) based on EVT is compared against several alternatives, such as historical simulation and analytical approach based on GARCH with a single conditional distribution. Model backtesting with daily returns shows that EVT-based models provide more reliable VaR and ES forecasts than the alternative models in all six markets. Unlike the alternatives, the EVT-based models cannot be rejected as VaR confidence level is increased. This emphasizes the importance of extreme events in SEE markets and indicates that the ability of a model to capture volatility clustering accurately is not sufficient for a correct assessment of risk in these markets.     

Information acquisition and mutual funds

We study the formation of mutual funds by generalizing the standard competitive noisy rational expectations framework. In our model, informed agents set up mutual funds as a means of selling their private information to uninformed agents. We study the case of imperfect competition among fund managers, where uninformed agents invest simultaneously in multiple mutual funds. The size of the assets under management in the mutual fund industry is determined by endogenizing the agents' information acquisition decisions. Our model yields novel predictions on the informativeness of price, the optimal fees of mutual funds, and the equilibrium risk premium. In particular, we show that a sufficiently competitive mutual fund sector yields more informative prices and a lower equity risk premium.     

Average drawdown risk reduction and risk tolerances

We investigate the effects of average drawdown risk reduction on US mutual funds. Due to numerous evidence of the asymmetric distribution of portfolio returns, the asymmetric risk measures have extensively been used in risk management during the recent decades with extensive usages on the n-degree lower partial moment (LPM) methodology. Unlike the previous literature, we use the n-degree average drawdown risk measure, which is a special case of n-degree LPM, to empirically investigate the impacts of n-degree average drawdown risk reduction on the risk tolerances generated by the US mutual funds.The evidence shows that skewness does not impose any significant problem on the n-degree A-DRM model. Moreover, the effect of changing the tolerances of average drawdown risk in the n-degree A-DRM models is a reduction in the fund returns. The n-degree CA-DRM optimization model reduces investors׳ risk more than other models. Thus, the A-DRM can be accommodated with risk-averse investors׳ approach. The efficient set of mean–variance choices from the investment opportunity set, as described by Markowitz, shows that the n-degree CA-DRM algorithms create this set with lower risk than other algorithms. It implies that the mean–variance opportunity set generated by the n-degree CA-DRM creates lower risk for a given return than covariance and CLPM.     

标准仓单质押组合的价格风险——基于中国农产品期货规范市场的实证研究

利用基于Copula函数的AR(p)-GARCH(p,q)模型计算的VaR能够对农产品标准仓单的价格风险进行准确度量。对大连商品交易所的典型期货交易品种——黄大豆一号、豆油、豆粕的期货合约日结算价进行了实证研究。研究结果显示:从对价格风险预测的盯市频率来看,时变VaR优于静态VaR,因此重视农产品价格风险的频次预测应替代传统风险判断的单次监测;从对风险因子间相依性结构的刻画来看,基于t-Copula函数计算的VaR优于基于正态Copula函数计算的VaR,因此质押物价格波动间的相关系数是度量组合风险时必须考虑的重要变量。