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1.
We use the two‐state Markov regime‐switching model to explain the behaviour of the WTI crude‐oil spot prices from January 1986 to February 2012. We investigated the use of methods based on the composite likelihood and the full likelihood. We found that the composite‐likelihood approach can better capture the general structural changes in world oil prices. The two‐state Markov regime‐switching model based on the composite‐likelihood approach closely depicts the cycles of the two postulated states: fall and rise. These two states persist for on average 8 and 15 months, which matches the observed cycles during the period. According to the fitted model, drops in oil prices are more volatile than rises. We believe that this information can be useful for financial officers working in related areas. The model based on the full‐likelihood approach was less satisfactory. We attribute its failure to the fact that the two‐state Markov regime‐switching model is too rigid and overly simplistic. In comparison, the composite likelihood requires only that the model correctly specifies the joint distribution of two adjacent price changes. Thus, model violations in other areas do not invalidate the results. The Canadian Journal of Statistics 41: 353–367; 2013 © 2013 Statistical Society of Canada  相似文献   

2.
In this paper, we obtain an adjusted version of the likelihood ratio (LR) test for errors-in-variables multivariate linear regression models. The error terms are allowed to follow a multivariate distribution in the class of the elliptical distributions, which has the multivariate normal distribution as a special case. We derive a modified LR statistic that follows a chi-squared distribution with a high degree of accuracy. Our results generalize those in Melo and Ferrari (Advances in Statistical Analysis, 2010, 94, pp. 75–87) by allowing the parameter of interest to be vector-valued in the multivariate errors-in-variables model. We report a simulation study which shows that the proposed test displays superior finite sample behavior relative to the standard LR test.  相似文献   

3.
This paper analyses adjustments in the Dutch retail gasoline prices. We estimate an error correction model on changes in the daily retail price for gasoline (taxes excluded) for the period 1996–2004, taking care of volatility clustering by estimating an EGARCH model. It turns out that the volatility process is asymmetrical: a positive shock to the retail price has a greater effect on the variance of the retail price than a negative shock. We conclude that the retail price and the spot price do not drift apart in the long run. However, there is a faster reaction to upward changes in spot prices than to downward changes in spot prices in the short run. This asymmetry starts 3 days after the change in the spot price and lasts for 4 days.  相似文献   

4.
ABSTRACT

We develop a new score-driven model for the joint dynamics of fat-tailed realized covariance matrix observations and daily returns. The score dynamics for the unobserved true covariance matrix are robust to outliers and incidental large observations in both types of data by assuming a matrix-F distribution for the realized covariance measures and a multivariate Student's t distribution for the daily returns. The filter for the unknown covariance matrix has a computationally efficient matrix formulation, which proves beneficial for estimation and simulation purposes. We formulate parameter restrictions for stationarity and positive definiteness. Our simulation study shows that the new model is able to deal with high-dimensional settings (50 or more) and captures unobserved volatility dynamics even if the model is misspecified. We provide an empirical application to daily equity returns and realized covariance matrices up to 30 dimensions. The model statistically and economically outperforms competing multivariate volatility models out-of-sample. Supplementary materials for this article are available online.  相似文献   

5.
《统计学通讯:理论与方法》2012,41(13-14):2545-2569
We study the general linear model (GLM) with doubly exchangeable distributed error for m observed random variables. The doubly exchangeable general linear model (DEGLM) arises when the m-dimensional error vectors are “doubly exchangeable,” jointly normally distributed, which is a much weaker assumption than the independent and identically distributed error vectors as in the case of GLM or classical GLM (CGLM). We estimate the parameters in the model and also find their distributions. We show that the tests of intercept and slope are possible in DEGLM as a particular case using parametric bootstrap as well as multivariate Satterthwaite approximation.  相似文献   

6.
This study examines the dynamics of the interrelation between option and stock markets using the Markov-switching vector error correction model. Specifically, we calculate the implied stock prices from the Black–Scholes 6 Black, F. and Scholes, M. 1973. The pricing of options and corporate liabilities. J. Polit. Econ., 81: 637659. [Crossref], [Web of Science ®] [Google Scholar] model and establish a statistic framework in which the parameter of the price discrepancy between the observed and implied prices switches according to the phase of the volatility regime. The model is tested in the US S&P 500 stock market. The empirical findings of this work are consistent with the following notions. First, while option markets react more quickly to the newest stock–option disequilibrium shocks than spot markets, as found by earlier studies, we further indicate that the price adjustment process occurring in option markets is pronounced when the high variance condition is concerned, but less so during the stable period. Second, the degree of the co-movement between the observed and implied prices is significantly reduced during the high variance state. Last, the lagged price deviation between the observed and implied prices functions as an indicator of the variance-turning process.  相似文献   

7.
Generally, the semiclosed-form option pricing formula for complex financial models depends on unobservable factors such as stochastic volatility and jump intensity. A popular practice is to use an estimate of these latent factors to compute the option price. However, in many situations this plug-and-play approximation does not yield the appropriate price. This article examines this bias and quantifies its impacts. We decompose the bias into terms that are related to the bias on the unobservable factors and to the precision of their point estimators. The approximated price is found to be highly biased when only the history of the stock price is used to recover the latent states. This bias is corrected when option prices are added to the sample used to recover the states' best estimate. We also show numerically that such a bias is propagated on calibrated parameters, leading to erroneous values. The Canadian Journal of Statistics 48: 8–35; 2020 © 2019 Statistical Society of Canada  相似文献   

8.
Summary Two quadratic formsS H andS E for a testable hypothesis and for an error in the multivariate Zyskind-Martin model with singular covariance matrix are expressed by means of projector operators. Thus the results for the multivariate standard model with identity covariance matrix given by Humak (1977) and Christensen (1987, 1991) are generalized for the case of Zyskind-Martin model. Special cases of our results are formulae forS H andS E in Aitken's (1935) model. In the case of general Gauss-Markoff modelS H andS E can also be expressed by means of projector operators for some subclasses of testable hypotheses. For these hypotheses, testing in Gauss-Markoff model is equivalent to testing in a Zyskind-Martin model.  相似文献   

9.
Hedonic price models are commonly used in the study of markets for various goods, most notably those for wine, art, and jewelry. These models were developed to estimate implicit prices of product attributes within a given product class, where in the case of some goods, such as wine, substantial product differentiation exists. To address this issue, recent research on wine prices employs local polynomial regression clustering (LPRC) for estimating regression models under class uncertainty. This study demonstrates that a superior empirical approach – estimation of a mixture model – is applicable to a hedonic model of wine prices, provided only that the dependent variable in the model is rescaled. The present study also catalogues several of the advantages over LPRC modeling of estimating mixture models.  相似文献   

10.
We consider the problem of estimating and testing a general linear hypothesis in a general multivariate linear model, the so-called Growth Curve model, when the p × N observation matrix is normally distributed.

The maximum likelihood estimator (MLE) for the mean is a weighted estimator with the inverse of the sample covariance matrix which is unstable for large p close to N and singular for p larger than N. We modify the MLE to an unweighted estimator and propose new tests which we compare with the previous likelihood ratio test (LRT) based on the weighted estimator, i.e., the MLE. We show that the performance of these new tests based on the unweighted estimator is better than the LRT based on the MLE.  相似文献   


11.
We propose an empirical framework to assess the likelihood of joint and conditional sovereign default from observed CDS prices. Our model is based on a dynamic skewed-t distribution that captures all salient features of the data, including skewed and heavy-tailed changes in the price of CDS protection against sovereign default, as well as dynamic volatilities and correlations that ensure that uncertainty and risk dependence can increase in times of stress. We apply the framework to euro area sovereign CDS spreads during the euro area debt crisis. Our results reveal significant time-variation in distress dependence and spill-over effects for sovereign default risk. We investigate market perceptions of joint and conditional sovereign risk around announcements of Eurosystem asset purchases programs, and document a strong impact on joint risk.  相似文献   

12.
《Econometric Reviews》2012,31(1):27-53
Abstract

Transformed diffusions (TDs) have become increasingly popular in financial modeling for their model flexibility and tractability. While existing TD models are predominately one-factor models, empirical evidence often prefers models with multiple factors. We propose a novel distribution-driven nonlinear multifactor TD model with latent components. Our model is a transformation of a underlying multivariate Ornstein–Uhlenbeck (MVOU) process, where the transformation function is endogenously specified by a flexible parametric stationary distribution of the observed variable. Computationally efficient exact likelihood inference can be implemented for our model using a modified Kalman filter algorithm and the transformed affine structure also allows us to price derivatives in semi-closed form. We compare the proposed multifactor model with existing TD models for modeling VIX and pricing VIX futures. Our results show that the proposed model outperforms all existing TD models both in the sample and out of the sample consistently across all categories and scenarios of our comparison.  相似文献   

13.
Publication of indexes measuring changes in prices of retail, wholesale, export, and import items is an important part of many governmental statistics programs. One form of price index that is often used is the fixed-base Laspeyres, in which a fixed market basket of goods is priced over time. This article introduces a new class of multiplicative estimators of Laspeyres indexes. The optimum within the class is derived for long-term price change and compared with two other members of the class when used for estimating both long-term and short-term change. Theoretical properties are derived under a model in which long-term relative price changes for individual items have common within-stratum means and are correlated over time. Theory for long-term and short-term change estimators is tested in a simulation study in which a large number of stratified probability samples is selected from a population extracted from items priced for the U.S. consumer price index.  相似文献   

14.
利用事件研究法,检验了《新闻联播》播报上市公司的新闻对该公司股价和交易量的影响,在此基础上,基于注意力理论,分别选择Google Trends搜索指数、公司市值规模作为投资者注意力、信息不对称程度的代理指标,构建了多元线性回归模型,研究股市异动的根源.检验结果表明:《新闻联播》导致了股市异动,股价在新闻报道后第2日出现0.36%的异常上涨,第3日至第15日发生0.92%的反转;交易量也在新闻后出现了1.87倍的异动.基于注意力理论的解释性研究表明:《新闻联播》所引起的股市异动,部分是由信息效应产生的,更关键的原因在于注意力驱动下的购买压力效应.此项研究丰富了行为金融的研究视域,并对投资者的投资决策提供了科学依据.  相似文献   

15.
This article reports on work designed to measure the time required for a change in a stock's price to be fully reflected in the price of a warrant on that stock. The method employed to measure the adjustment speed is the bivariate transfer function technique of Box and Jenkins. An interesting aspect of the study is the use of trade-by-trade data for measuring stock and warrant returns. The evidence presented here suggests that warrant prices adjust quickly to changes in stock prices. In addition, evidence concerning the ability of the estimated models to forecast warrant prices is presented.  相似文献   

16.
对多变量时间序列进行预测,单变量ARIMA模型和普通多元回归分析并不适用,这种情况下应用多变量ARIMA即传递函数模型是很好的选择。以一种受原油和原材料多种因素影响的合成化纤产品为例,说明利用传递函数模型对其价格进行预测的建模过程中,如何进行模型识别、参数估计及诊断的有关问题。  相似文献   

17.
Abstract. Maximum likelihood estimation in many classical statistical problems is beset by multimodality. This article explores several variations of deterministic annealing that tend to avoid inferior modes and find the dominant mode. In Bayesian settings, annealing can be tailored to find the dominant mode of the log posterior. Our annealing algorithms involve essentially trivial changes to existing optimization algorithms built on block relaxation or the EM or MM principle. Our examples include estimation with the multivariate t distribution, Gaussian mixture models, latent class analysis, factor analysis, multidimensional scaling and a one‐way random effects model. In the numerical examples explored, the proposed annealing strategies significantly improve the chances for locating the global maximum.  相似文献   

18.
In this paper, we propose an extension of the Merton short rate model, which reflects the subdiffusive nature of the short rate dynamics. The subdiffusive property is manifested by the random periods of time, during which the asset price does not change. We derive explicit formulas for European call and put options and present some simulation results for the case of α stable. Moreover, we discuss the implied volatility of this model.  相似文献   

19.
The theoretical price of a financial option is given by the expectation of its discounted expiry time payoff. The computation of this expectation depends on the density of the value of the underlying instrument at expiry time. This density depends on both the parametric model assumed for the behaviour of the underlying, and the values of parameters within the model, such as volatility. However neither the model, nor the parameter values are known. Common practice when pricing options is to assume a specific model, such as geometric Brownian Motion, and to use point estimates of the model parameters, thereby precisely defining a density function.We explicitly acknowledge the uncertainty of model and parameters by constructing the predictive density of the underlying as an average of model predictive densities, weighted by each model's posterior probability. A model's predictive density is constructed by integrating its transition density function by the posterior distribution of its parameters. This is an extension to Bayesian model averaging. Sampling importance-resampling and Monte Carlo algorithms implement the computation. The advantage of this method is that rather than falsely assuming the model and parameter values are known, inherent ignorance is acknowledged and dealt with in a mathematically logical manner, which utilises all information from past and current observations to generate and update option prices. Moreover point estimates for parameters are unnecessary. We use this method to price a European Call option on a share index.  相似文献   

20.
This paper introduces a new information-theoretic measure of complexity called ICOMP as a decision rule for model selection and evaluation for multivariate linear models. The development of ICOMP is based on the generalization and utilization of the covariance complexity index of van Emden (1971) in estimation of the multivariate linear model. ICOMP is motivated by Akaike's (1973) Information Criterion (AIC), but it is a different procedure than AIC. In linear or nonlinear statistical models ICOMP uses an information-based characterization of: (i) the covariance matrix properties of the parameter estimates of a model starting from their finite sampling distributions, and (ii) the complexity of the inverse-Fisher information matrix (i-FIM) as a new criterion of achievable accuracy of the model As a result, it provides a trade-off between the accuracy of the parameter estimates and the interaction of the residuals of a model via the measure of complexity of their respective covariances. It controls the risks of both insufficient and overparameterized models, and incorporates the assumption of dependence and the independence of the residuals in one criterion function. A model with minimum ICOMP is chosen to be the best model among all possible competing alternative models. ICOMP relieves the researcher of any need to consider the parameter dimension of a model explicitly. A real numerical example is shown in subset selection of variables in multivariate regression analysis to demonstrate the utility and versatility of the new approach.  相似文献   

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