GARCH模型能否提供好的波动率预测

由于波动率在投资、期权定价等方面极为重要,近20年来,预测金融市场的波动率已成为金融领域理论上和实证上的热门话题。本文详细讨论了预测波动率的几个常用的模型和衡量指标,并回顾了这方面的文献。运用模型分析了1999～2004年欧元、日元、英镑、澳元等四种货币兑美元的汇率。最后进行波动率的预测并对各种预测效果进行评估。     

波动率预测:GARCH模型与隐含波动率

在预测未来波动率时,究竟是基于历史数据的时间序列模型还是基于期权价格的隐含波动率模型效率更高?本文对香港恒生指数期权市场所含信息的研究发现,在预测期限较短(一周)时,GARCH(1,1)模型所含信息较多,预测能力最强,但在预测较长期限(一个月)时,隐含波动率所含信息较多,预测能力较强。同时,期权市场交易越活跃,所反映的信息就越全面,隐含波动率的预测能力也就越强。     

GARCH族的模型平均估计方法

研究目标：对模型平均方法进行理论扩展,构建GARCH族的模型平均估计量及相应权重选择准则。研究方法：蒙特卡洛模拟实验方法。研究发现：在一定条件下最小化权重准则选择的权重向量将在渐近意义上最小化真实KL偏离度;蒙特卡洛模拟结果表明,与AIC准则、BIC准则、AIC模型平均、BIC模型平均的估计结果相比较,本文提出的模型平均法具有更小的KL偏离度。研究创新：将模型平均估计方法引入条件异方差模型族中。研究价值：本文结果将为捕捉金融市场资产的时变波动性提供强有力的研究工具。     

基于不同分布假设GARCH模型对上证指数波动性预测能力的比较研究

本文在四种不同的分布假设(Normal,Student-t,GED和SkewedStudent-t)下,对上证指数波动性进行了GARCH(1,1)模型预测能力实证比较研究,目的在于揭示分布假设对GARCH模型预测能力的影响。研究结果表明,使用厚尾分布假设(Student-t,GED)提高了模型的预测绩效。但引入偏斜student-t分布并未能进一步提高模型预测能力。     

非参数GARCH模型对沪深股市的实证分析

利用非参数GARCH模型对沪深股市2000年1月4日至2009年12月31日每日收盘指数的对数收益率进行实证分析,并与参数GARCH模型估计结果进行对比,发现非参数GARCH模型拟合的波动率比参数GARCH模型更接近实际情况。     

基于不同分布假设GARCH模型对上证指数波动性预测能力的比较研究

本文在四种不同的分布假设(Normal,Student-t,GED和Skewed Student-t)下,对上证指数波动性进行了GARCH(1,1)模型预测能力实证比较研究,目的在于揭示分布假设对GARCH模型预测能力的影响.研究结果表明,使用厚尾分布假设(Student-t,GED)提高了模型的预测绩效.但引入偏斜student-t分布并未能进一步提高模型预测能力.     

EWMA-GARCH模型与GARCH模型在估计收益率波动上的差异的实证及理论分析

VaR作为衡量风险的指标,其核心则在于对波动,亦即方差的估计。基于时间序列,关于条件方差的经典模型是GARCH模型,尽管后来又衍生出了EGARCH,PARCH等复杂模型,但在实务中GARCH模型仍占有重要的地位。文章分析了一种比较新的结合了EWMA模型的GARCH模型(以下称为EWMA-GARCH模型)计算VaR的参数估计方法,以检验其在估计波动上的实用性,并对实证检验结果做了理论分析。分析结果表明,尽管该结合模型缺乏完整的理论支持,但是其计算效果仍比较良好,当然这样良好的结果是建立在因缺乏理论依据而导致的对模型的其他要求之上的.至于是采用受理论支持的模型还是并不输实践价值的模型,文章也给出了一定的建议。     

基于GARCH模型族的上证综指实证研究

早在20世纪60年代,Fama（1965）观察到投机性价格的变化和收益率的变化具有稳定时期和易变时期,大的报酬紧连着大的报酬,小的报酬紧连着小的报酬,称为波动集群性（Mandelbrot,1963;Fama,1965）。此后,国外开始对投机性价格波动特征进行了大量研究,其中Engle（1982）提出的自回归条件异方差性模型（即ARCH模型）很好地捕获条件异方差性以及尖峰厚尾性,拟合了波动率聚类现象。     

汇率基本面模型对人民币汇率的预测能力

本文选取五个主流的汇率基本面模型,使用2005年汇改后的人民币兑美元、欧元、日元、英镑汇率数据进行样本内拟合和样本外预测,并通过计算损失函数和SPA统计量比较五种模型的预测能力。实证结果表明：随机游走模型短期内具有更优的预测能力,但中长期内,汇率基本面模型具有更优的预测能力;总体来讲,汇率基本面模型的预测能力优于随机游走模型,人民币汇率不存在“汇率失联之谜”;对不同的货币,具有最优预测能力的模型不同。     

基于GARCH模型的股票收益率分析及预测

GARCH模型是对金融数据波动性进行描述的有效方法,它是最常用、最便捷的异方差序列拟合模型。资产收益率是金融数据分析常用的指标,比价格序列更易处理且更有研究意义。本文采用R语言,对2009年1月6日—2019年5月20日沪深300指数的日收盘价进行预处理,将其转化为平稳的收益率序列,检验其ARCH效应,建立GARCH模型以及标准化残差分析,最后对收益率和股票价格进行预测,预测的结果能为投资者进行决策提供一定的参考。     

Using neural network to forecast stock index option price: a new hybrid GARCH approach

This study aims to apply a new hybrid approach to estimate volatility in neural network option-pricing model. The analytical results also indicate that the new hybrid method can be used to forecast the prices of derivative securities. Owing to combines the grey forecasting model with the GARCH to improve the estimated ability, the empirical evidence shows that the new hybrid GARCH model outperforms the other approaches in the neural network option-pricing model.     

对上证指数波动性的实证分析

股票价格频繁波动是股票市场中最明显的特征之一。ARCH类模型可以成功的预测金融资产收益的方差。通过对我国股价指数的统计描述,表明我国金融资产收益率存在自回归条件异方差,并表现出非正态性。并且应用GARCH、TARCH、EGARCH模型理论,进一步分析了日收益率波动的条件异方差性、非对称性。     

Forecasting the volatility of asset returns: The informational gains from option prices

A new class of forecasting models is proposed that extends the realized GARCH class of models through the inclusion of option prices to forecast the variance of asset returns. The VIX is used to approximate option prices, resulting in a set of cross-equation restrictions on the model’s parameters. The full model is characterized by a nonlinear system of three equations containing asset returns, the realized variance, and the VIX, with estimation of the parameters based on maximum likelihood methods. The forecasting properties of the new class of forecasting models, as well as a number of special cases, are investigated and applied to forecasting the daily S&P500 index realized variance using intra-day and daily data from September 2001 to November 2017. The forecasting results provide strong support for including the realized variance and the VIX to improve variance forecasts, with linear conditional variance models performing well for short-term one-day-ahead forecasts, whereas log-linear conditional variance models tend to perform better for intermediate five-day-ahead forecasts.     

Comparing Aspiration Models: The Role of Selective Attention

For many years, scholars have used a variety of models to measure organizational aspirations, but these alternative measures reflect differing assumptions about the decision‐making processes determining aspiration levels. This study begins by examining some of the implications of the aspiration models in use. It then extends the theoretical model of aspiration levels from the behavioural theory of the firm to incorporate varying attention, another fundamental concept from the theory. Finally, it uses direct aspiration measures on the sales performance of retailers in a large automotive manufacturer to assess the alternative theories by comparing existing models with one that incorporates varying attention. We find support for a model where the importance of the factors influencing aspiration levels varies with the level of past firm performance relative to industry performance. Thus, the varying attention so central to the behavioural theory of the firm influences the formulation of aspirations.     

基于GARCH族模型的黄金价格收益率及波动性研究

文章应用GARCH族模型对黄金现货价格的收益率及波动性进行实证研究,实证结果表明黄金价格日收益率具有"尖峰厚尾"和"波动聚类"的特征。通过TGARCH及EGARCH模型发现我国黄金市场存在非对称性现象,正的冲击对黄金价格波动影响更大。     

单位根检验统计量MGLS的有限样本性质与应用

Ng—Perron单位根检验是值得在实际分析中广泛应用的检验方法。本文在详述M^GLS统计量的构造方法基础上,应用蒙特卡罗模拟试验分析了该统计量的有限样本分布特征,并拟合了常用显著性水平下临界值关于样本容量的响应面函数;此外,针对实际应用中检验回归式中差分变量滞后阶数的确定,本文总结了几种常用的方法,从而完善了依据M^GLS统计量进行单位根检验的程序和步骤。     

Introducing Environmental Variables in Nonparametric Frontier Models: a Probabilistic Approach

This paper proposes a general formulation of a nonparametric frontier model introducing external environmental factors that might influence the production process but are neither inputs nor outputs under the control of the producer. A representation is proposed in terms of a probabilistic model which defines the data generating process. Our approach extends the basic ideas from Cazals et al. (2002) to the full multivariate case. We introduce the concepts of conditional efficiency measure and of conditional efficiency measure of order-m. Afterwards we suggest a practical way for computing the nonparametric estimators. Finally, a simple methodology to investigate the influence of these external factors on the production process is proposed. Numerical illustrations through some simulated examples and through a real data set on Mutual Funds show the usefulness of the approach.JEL Classification: C13, C14, D20     

Shock and volatility spillovers among equity sectors of the Gulf Arab stock markets

The major objectives of this study are twofold. The first objective is to examine the dynamic volatility and volatility transmission in a multivariate setting using the VAR(1)–GARCH(1,1) model for three major sectors, namely, Service, Banking and Industrial/or Insurance, in four Gulf Cooperation Council (GCC)’s economies (Kuwait, Qatar, Saudi Arabia and UAE). The second is to use the models’ results to compute and analyze the optimal weights and hedge ratios for two-sector portfolio holdings, comprised of the three sectors for each country. The results suggest that past own volatilities matter more than past shocks and there are moderate volatility spillovers between the sectors within the individual countries, with the exception of Qatar. Moreover, the values for ratios of hedging long positions with short positions in the GCC sectors are smaller than those for the US equity sectors. The optimal portfolio weights favor the Banking/financial sector for Qatar, Saudi Arabia and UAE and the Industrial sector for Kuwait.