Based on the complex network theory,this paper studies the systemic financial risks in China’s financial market.According to the industry classification of the China Securities Regulatory Commission in 2012,the daily...Based on the complex network theory,this paper studies the systemic financial risks in China’s financial market.According to the industry classification of the China Securities Regulatory Commission in 2012,the daily closing prices of 45 listed financial institutions are collected and the daily return rates of each financial institution are measured according to the logarithmic return rate calculation formula.In this paper,the risk spillover value ΔCoVaR is used to measure the contribution degree of each financial institution to systemic risk.Finally,the relationship between the risk spillover valueΔCoVaR and the node topology index of the risk transmission network is investigated by using a regression model,and some policy suggestions are put forward based on the regression results.展开更多
We introduce a new wavelet based procedure for detecting outliers in financial discrete time series.The procedure focuses on the analysis of residuals obtained from a model fit,and applied to the Generalized Autoregre...We introduce a new wavelet based procedure for detecting outliers in financial discrete time series.The procedure focuses on the analysis of residuals obtained from a model fit,and applied to the Generalized Autoregressive Conditional Heteroskedasticity(GARCH)like model,but not limited to these models.We apply the Maximal-Overlap Discrete Wavelet Transform(MODWT)to the residuals and compare their wavelet coefficients against quantile thresholds to detect outliers.Our methodology has several advantages over existing methods that make use of the standard Discrete Wavelet Transform(DWT).The series sample size does not need to be a power of 2 and the transform can explore any wavelet filter and be run up to the desired level.Simulated wavelet quantiles from a Normal and Student t-distribution are used as threshold for the maximum of the absolute value of wavelet coefficients.The performance of the procedure is illustrated and applied to two real series:the closed price of the Saudi Stock market and the S&P 500 index respectively.The efficiency of the proposed method is demonstrated and can be considered as a distinct important addition to the existing methods.展开更多
A statistical manifold of non-exponential type coming from a model for economics describing stock return process is constructed, with its geometric structure investigated and both Gaussian curvatures and mean curvatur...A statistical manifold of non-exponential type coming from a model for economics describing stock return process is constructed, with its geometric structure investigated and both Gaussian curvatures and mean curvatures of its curved exponential submanifolds deducted. A few graphs describing relevant scalar curvature, mean curvature and Gaussian curvature are also introduced.展开更多
This paper discusses the model construction and the association between the Italy and the Germany's stock markets. The period of study data is from January 3, 2000 to June 30, 2008. This paper also utilizes Student'...This paper discusses the model construction and the association between the Italy and the Germany's stock markets. The period of study data is from January 3, 2000 to June 30, 2008. This paper also utilizes Student's t distribution to analyze the proposed model. The empirical results show that the two stock markets are mutually affected each other, and the dynamic conditional correlation (DCC) and the bivariate asymmetric-GARCH (1, 2) model is appropriate in evaluating the relation between them. The empirical result also indicates that Italy and Germany's stock markets show a positive relationship. The average value of correlation coefficient equals to 0.8424, which implies that the two stock markets return volatility have a synchronized influence on each other. In addition, the empirical result also shows that there is an asymmetrical effect between Italy and the Germany's stock markets, and demonstrates that the good news and bad news of the stock returns' volatility will produce the different variation risks for Italy and the Germany's stock price markets.展开更多
This study focuses on the Indian gold futures market where primary participants hold sentimental value for the underlying asset and are globally ranked number two in terms of the largest private holdings in the physic...This study focuses on the Indian gold futures market where primary participants hold sentimental value for the underlying asset and are globally ranked number two in terms of the largest private holdings in the physical form.The trade of gold futures relates to seasons,festivity,and government policy.So,the paper will discuss seasonality and intervention in the analysis.Due to non-constant variance,we will also use the standard variance stabilization transformation method and the ARIMA/GARCH modelling method to compare the forecast performance on the gold futures prices.The results from the analysis show that while the standard variance transformation method may provide better point forecast values,the ARIMA/GARCH modelling method provides much shorter forecast intervals.The empirical results of this study which rationalise the effect of seasonality in the Indian bullion derivative market have not been reported in literature.展开更多
This paper compares the stock return distribution models of mixture normal distribution, mixed diffusion-jump and GARCH models based on the data of Chinese stock market. The Schwarz criterion is also used. We find all...This paper compares the stock return distribution models of mixture normal distribution, mixed diffusion-jump and GARCH models based on the data of Chinese stock market. The Schwarz criterion is also used. We find all these models can capture the features of stock returns partly. EGARCH model is the best fitting to daily return and stable during different period. When the weekly and monthly returns are tested, the differences of the models' fitness become unobvious and unstable.展开更多
the model in time series analysis are widely used in the field of economy. We often use the model in time series to analyze data, but without regard to the rationality of the model. In this paper, we introduce and ana...the model in time series analysis are widely used in the field of economy. We often use the model in time series to analyze data, but without regard to the rationality of the model. In this paper, we introduce and analyze Ping An Of China(601318) shares at the opening price(2013/01/04-2013/07/04).The model is established by analyzing data. Modeling steps of ARIMA model and GARCH model are presented in this paper. The data whether ARIMA model is suitable by white noise. Or the data whether GARCH model is suitable by since the correlation of variance test. By comparing the analysis, it selects a more reasonable model.展开更多
This paper examines the forecasting performance of different kinds of GARCH model (GRACH, EGARCH, TARCH and APARCH) under the Normal, Student-t and Generalized error distributional assumption. We compare the effect ...This paper examines the forecasting performance of different kinds of GARCH model (GRACH, EGARCH, TARCH and APARCH) under the Normal, Student-t and Generalized error distributional assumption. We compare the effect of different distributional assumption on the GARCH models. The data we analyze are the daily stocks indexes for Shenzhen Stock Exchange (SSE) in China from April 3^rd, 1991 to April 14^th, 2005. We find that improvements of the overall estimation are achieved when asymmetric GARCH models are used with student-t distribution and generalized error distribution. Moreover, it is found that TARCH and GARCH models give better forecasting performance than EGARCH and APARCH models. In forecasting performance, the model under normal distribution gives more accurate forecasting performance than non-normal densities and generalized error distributions clearly outperform the student-t densities in case of SSE.展开更多
A suitable statistical model has been explored for the investors as well as the researchers to resolve the future estimation of share volume by using daily stock volume data from Dhaka Stock Exchange (DSE). The dail...A suitable statistical model has been explored for the investors as well as the researchers to resolve the future estimation of share volume by using daily stock volume data from Dhaka Stock Exchange (DSE). The daily volume data from the June 1, 2004 to April 19, 2010 were retrieved from DSE website as a secondary data source. The Maximum Likelihood---Autoregressive Conditional Heteroskedasticity (ARCH) (Marquardt) method has been applied to construct the models for the stock volume data of DSE by using statistical package software E-Views of verson-5. First of all, an "Auto Regressive Integrated Moving Average (ARIMA) model" was fitted and observed that heteroscedastic volatilities were still present there. To eliminate this dilemma, ARCH class of volatility models has been used and finally the ARIMA with EGARCH model has been explored. Findings of this study have recognized that ARIMA with EGARCH model implies low mean square error, low mean absolute error, low bias proportion, and low variance proportion for share volume data with comparing to other models. Hence, the modelling concept established in this study would be a decisive study for the investors as well as the researchers.展开更多
Since the establishment of financial models for risk prediction,the measurement of volatility at risky market has improved,and its significance has also grown.For high-frequency financial data,the degree of investment...Since the establishment of financial models for risk prediction,the measurement of volatility at risky market has improved,and its significance has also grown.For high-frequency financial data,the degree of investment risk,which has always been the focus of attention,is measured by the variance of residual sequence obtained following model regression.By integrating the long short-term memory(LSTM)model with multiple generalized autoregressive conditional heteroscedasticity(GARCH)models,a new hybrid LSTM model is used to predict stock price volatility.In this paper,three GARCH models are used,and the model that can best fit the data is determined.展开更多
The financial market is the core of national economic development,and stocks play an important role in the financial market.Analyzing stock prices has become the focus of investors,analysts,and people in related field...The financial market is the core of national economic development,and stocks play an important role in the financial market.Analyzing stock prices has become the focus of investors,analysts,and people in related fields.This paper evaluates the volatility of Apple Inc.(AAPL)returns using five generalized autoregressive conditional heteroskedasticity(GARCH)models:sGARCH with constant mean,GARCH with sstd,GJR-GARCH,AR(1)GJR-GARCH,and GJR-GARCH in mean.The distribution of AAPL’s closing price and earnings data was analyzed,and skewed student t-distribution(sstd)and normal distribution(norm)were used to further compare the data distribution of the five models and capture the shape,skewness,and loglikelihood in Model 4-AR(1)GJR-GARCH.Through further analysis,the results showed that Model 4,AR(1)GJR-GARCH,is the optimal model to describe the volatility of the return series of AAPL.The analysis of the research process is both,a process of exploration and reflection.By analyzing the stock price of AAPL,we reflect on the shortcomings of previous analysis methods,clarify the purpose of the experiment,and identify the optimal analysis model.展开更多
Forecasting returns for the Artificial Intelligence and Robotics Index is of great significance for financial market stability,and the development of the artificial intelligence industry.To provide investors with a mo...Forecasting returns for the Artificial Intelligence and Robotics Index is of great significance for financial market stability,and the development of the artificial intelligence industry.To provide investors with a more reliable reference in terms of artificial intelligence index investment,this paper selects the NASDAQ CTA Artificial Intelligence and Robotics(AIRO)Index as the research target,and proposes innovative hybrid methods to forecast returns by considering its multiple structural characteristics.Specifically,this paper uses the ensemble empirical mode decomposition(EEMD)method and the modified iterative cumulative sum of squares(ICSS)algorithm to decompose the index returns and identify the structural breakpoints.Furthermore,it combines the least-square support vector machine approach with the particle swarm optimization method(PSO-LSSVM)and the generalized autoregressive conditional heteroskedasticity(GARCH)type models to construct innovative hybrid forecasting methods.On the one hand,the empirical results indicate that the AIRO index returns have complex structural characteristics,and present time-varying and nonlinear characteristics with high complexity and mutability;on the other hand,the newly proposed hybrid forecasting method(i.e.,the EEMD-PSO-LSSVM-ICSS-GARCH models)which considers these complex structural characteristics,can yield the optimal forecasting performance for the AIRO index returns.展开更多
By using GARCH(1,1)-M and EGARCH(1,1)-M models, the relationships among funds speculation transaction, arbitrage transaction and the fluctuation of international copper future price were studied. The news impact c...By using GARCH(1,1)-M and EGARCH(1,1)-M models, the relationships among funds speculation transaction, arbitrage transaction and the fluctuation of international copper future price were studied. The news impact curve of copper future price fluctuation respectively introduced funds speculation position and arbitrage position was given, and the result is consistent with the empirical study conclusion. The results show that investment funds are not the factor that causes copper future price fluctuation, but can reduce the copper future price fluctuation; the copper future price fluctuation is more sensitive to negative information, and ftmd speculative positions can reduce asymmetric effect of copper price fluctuation, while fimds arbitrage position influences less.展开更多
Natural ventilation is driven by either buoyancy forces or wind pressure forces or their combinations that inherit stochastic variation into ventilation rates. Since the ventilation rate is a nonlinear function of mul...Natural ventilation is driven by either buoyancy forces or wind pressure forces or their combinations that inherit stochastic variation into ventilation rates. Since the ventilation rate is a nonlinear function of multiple variable factors including wind speed, wind direction, internal heat source and building structural thermal mass, the conventional methods for quantifying ventilation rate simply using dominant wind direction and average wind speed may not accurately describe the characteristic performance of natural ventilation. From a new point of view, the natural ventilation performance of a single room building under fluctuating wind speed condition using the Monte-Carlo simulation approach was investigated by incorporating building facade thermal mass effect. Given a same hourly turbulence intensity distribution, the wind speeds with 1 rain frequency fluctuations were generated using a stochastic model, the modified GARCH model. Comparisons of natural ventilation profiles, effective ventilation rates, and air conditioning electricity use for a three-month period show statistically significant differences (for 80% confidence interval) between the new calculations and the traditional methods based on hourly average wind speed.展开更多
This paper uses a Value at Risk (VaR) approach to evaluate a country financial vulnerability, by analyzing the risk exposure of its Central Bank, as if their assets are subject to market risk. The Brazilian currency...This paper uses a Value at Risk (VaR) approach to evaluate a country financial vulnerability, by analyzing the risk exposure of its Central Bank, as if their assets are subject to market risk. The Brazilian currency exchange swaps contracts (USS/Brazilian Reais) are submitted to a delta-normal VaR method, in order to evaluate the market risk of each swaps series, by modeling the variance of the daily returns, from August 1999 to January 2003. All daily returns series exhibited heteroscedasticity in the conditional variance and sudden changes in the unconditional variance. The points of changes of the unconditional variance were determined through the Iterative Cumulative Sum of Squares (ICSS) algorithm, and the conditional variance was modeled with Markov-Switching-Generalized Autoregressive Conditional Heteroscedasticity (SWGARCH) in order to capture heteroscedasticity and regime change. The results lead to two main conclusions: First, a VaR model must incorporate heteroscedasticity and regime switching in order to describe the variance of the tested series, submitted to brisk changes of economic and political scenarios. Second, a volatility-based VaR do not necessarily generate forward-looking indicators, but rather coincident indicators of possible financial vulnerabilities. The future research will evolve towards evaluating the effects of the Basel III recommendations as if they could be applied to this crisis period.展开更多
Gold is always a precious metal for many hundred years. Semi flexible gold demand and supply chain determines international gold prices in the long term. USA is ranked the world’s largest gold producer. This study ma...Gold is always a precious metal for many hundred years. Semi flexible gold demand and supply chain determines international gold prices in the long term. USA is ranked the world’s largest gold producer. This study mainly aims to investigate the dynamic factors which affect the price of gold and determine the essential macro-economic variable that has the most important role during the process. This paper examines USA over 13 years applying a formal test for time series, which interrogate cointegration relationships, what is the affiliation between gold price and other factors, which are explained in detail below. The present study has used the monthly data from January, 2003 to June, 2016. Databases are provided by the Federal Reserve, the central bank of the United States, and United States Energy Information Administration. Data analysis was performed with software package EViews 8. Through the time series, an analysis has been carried out on Dow Jones Index, the US exchange rate, silver price, interest rate, oil price and inflation rate which are thought to influence the price of gold in the most significant way. The data analysis includes the determination of the conditional heteroscedastic model to estimate volatility. Therefore, the best fitting model to the data set, which is the exponential GARCH model, is preferred. In accordance with the results of the empirical analyses in the USA, the highest negative correlation is found between gold prices and US exchange rate. Secondly, a positive correlation is found among gold prices, silver prices, and oil prices. Another point which takes attention as a result of the study is that economic and political structural breaks weighed heavily, traders and hedgers from all over the world were able to drive prices up to incredible highs. The added valueof our study arises from the inclusion in the analysis of macro economic variables, which has proved to have crucial relevance for the price of gold in the context of the recent economic structure.展开更多
Margin rules are very important rules in futures market. This paper provides a new Value-at-Risk (VaR) approach which uses GARCH model to set margin levels. The new approach overcomes the limitation of the hypothesi...Margin rules are very important rules in futures market. This paper provides a new Value-at-Risk (VaR) approach which uses GARCH model to set margin levels. The new approach overcomes the limitation of the hypothesis of normal distribution in traditional methods and improves the estimation precision. We use the data of metal futures in China's Shanghai Futures Exchange (SHFE) to have an empirical study.展开更多
Uncertainty analysis and risk analysis are two important areas of modern water resource management,in which accurate variance estimation is required.The traditional runoff model is established under the assumption tha...Uncertainty analysis and risk analysis are two important areas of modern water resource management,in which accurate variance estimation is required.The traditional runoff model is established under the assumption that the variance is a constant or it changes with the seasons.However,hydrological processes in the real world are often heteroscedastic,which can be tested by McLeod-Li test and Engle Lagrange multiplier test.In such cases,the GARCH model of hydrological processes is established in this article.First,the seasonal factors in the sequence are removed.Second,the traditional ARMA model is established.Then,the GARCH model is used to correct the residual.At last,the daily runoff data in 1949-2001 of Yichang Hydrological Station is taken to be an example.The result shows that compared to the traditional ARMA model,the GARCH model has the ability to predict more accurate confidence intervals under the same confidence level.展开更多
This paper investigates the mean-reversion and volatile of credit spread time series by using regression and time series analysis in Chinese bond market. Then the Longstaff-Schwartz model and GARCH model are applied t...This paper investigates the mean-reversion and volatile of credit spread time series by using regression and time series analysis in Chinese bond market. Then the Longstaff-Schwartz model and GARCH model are applied to price credit spread put option. The authors compare the features of these two models by employing daily bond prices of government bonds and corporate bonds for the period 2010–2012 in Chinese bond market. The proposed results show that the higher the credit ratings of the corporate bonds are, the lower the prices of the credit spread options are.展开更多
Wind power forecasting is of great significance to the safety, reliability and stability of power grid. In this study, the GARCH type models are employed to explore the asymmetric features of wind power time series an...Wind power forecasting is of great significance to the safety, reliability and stability of power grid. In this study, the GARCH type models are employed to explore the asymmetric features of wind power time series and improved forecasting precision. Benchmark Symmetric Curve (BSC) and Asymmetric Curve Index (ACI) are proposed as new asymmetric volatility analytical tool, and several generalized applications are presented. In the case study, the utility of the GARCH-type models in depicting time-varying volatility of wind power time series is demonstrated with the asymmetry effect, verified by the asymmetric parameter estimation. With benefit of the enhanced News Impact Curve (NIC) analysis, the responses in volatility to the magnitude and the sign of shocks are emphasized. The results are all confirmed to be consistent despite varied model specifications. The case study verifies that the models considering the asymmetric effect of volatility benefit the wind power forecasting performance.展开更多
文摘Based on the complex network theory,this paper studies the systemic financial risks in China’s financial market.According to the industry classification of the China Securities Regulatory Commission in 2012,the daily closing prices of 45 listed financial institutions are collected and the daily return rates of each financial institution are measured according to the logarithmic return rate calculation formula.In this paper,the risk spillover value ΔCoVaR is used to measure the contribution degree of each financial institution to systemic risk.Finally,the relationship between the risk spillover valueΔCoVaR and the node topology index of the risk transmission network is investigated by using a regression model,and some policy suggestions are put forward based on the regression results.
文摘We introduce a new wavelet based procedure for detecting outliers in financial discrete time series.The procedure focuses on the analysis of residuals obtained from a model fit,and applied to the Generalized Autoregressive Conditional Heteroskedasticity(GARCH)like model,but not limited to these models.We apply the Maximal-Overlap Discrete Wavelet Transform(MODWT)to the residuals and compare their wavelet coefficients against quantile thresholds to detect outliers.Our methodology has several advantages over existing methods that make use of the standard Discrete Wavelet Transform(DWT).The series sample size does not need to be a power of 2 and the transform can explore any wavelet filter and be run up to the desired level.Simulated wavelet quantiles from a Normal and Student t-distribution are used as threshold for the maximum of the absolute value of wavelet coefficients.The performance of the procedure is illustrated and applied to two real series:the closed price of the Saudi Stock market and the S&P 500 index respectively.The efficiency of the proposed method is demonstrated and can be considered as a distinct important addition to the existing methods.
基金Sponsored by the National Natural Science Foundation of China(10871218)
文摘A statistical manifold of non-exponential type coming from a model for economics describing stock return process is constructed, with its geometric structure investigated and both Gaussian curvatures and mean curvatures of its curved exponential submanifolds deducted. A few graphs describing relevant scalar curvature, mean curvature and Gaussian curvature are also introduced.
文摘This paper discusses the model construction and the association between the Italy and the Germany's stock markets. The period of study data is from January 3, 2000 to June 30, 2008. This paper also utilizes Student's t distribution to analyze the proposed model. The empirical results show that the two stock markets are mutually affected each other, and the dynamic conditional correlation (DCC) and the bivariate asymmetric-GARCH (1, 2) model is appropriate in evaluating the relation between them. The empirical result also indicates that Italy and Germany's stock markets show a positive relationship. The average value of correlation coefficient equals to 0.8424, which implies that the two stock markets return volatility have a synchronized influence on each other. In addition, the empirical result also shows that there is an asymmetrical effect between Italy and the Germany's stock markets, and demonstrates that the good news and bad news of the stock returns' volatility will produce the different variation risks for Italy and the Germany's stock price markets.
基金supported by the Fulbright-Nehru Doctoral Research program(Award No.2447/DR/2019-2020).
文摘This study focuses on the Indian gold futures market where primary participants hold sentimental value for the underlying asset and are globally ranked number two in terms of the largest private holdings in the physical form.The trade of gold futures relates to seasons,festivity,and government policy.So,the paper will discuss seasonality and intervention in the analysis.Due to non-constant variance,we will also use the standard variance stabilization transformation method and the ARIMA/GARCH modelling method to compare the forecast performance on the gold futures prices.The results from the analysis show that while the standard variance transformation method may provide better point forecast values,the ARIMA/GARCH modelling method provides much shorter forecast intervals.The empirical results of this study which rationalise the effect of seasonality in the Indian bullion derivative market have not been reported in literature.
文摘This paper compares the stock return distribution models of mixture normal distribution, mixed diffusion-jump and GARCH models based on the data of Chinese stock market. The Schwarz criterion is also used. We find all these models can capture the features of stock returns partly. EGARCH model is the best fitting to daily return and stable during different period. When the weekly and monthly returns are tested, the differences of the models' fitness become unobvious and unstable.
文摘the model in time series analysis are widely used in the field of economy. We often use the model in time series to analyze data, but without regard to the rationality of the model. In this paper, we introduce and analyze Ping An Of China(601318) shares at the opening price(2013/01/04-2013/07/04).The model is established by analyzing data. Modeling steps of ARIMA model and GARCH model are presented in this paper. The data whether ARIMA model is suitable by white noise. Or the data whether GARCH model is suitable by since the correlation of variance test. By comparing the analysis, it selects a more reasonable model.
文摘This paper examines the forecasting performance of different kinds of GARCH model (GRACH, EGARCH, TARCH and APARCH) under the Normal, Student-t and Generalized error distributional assumption. We compare the effect of different distributional assumption on the GARCH models. The data we analyze are the daily stocks indexes for Shenzhen Stock Exchange (SSE) in China from April 3^rd, 1991 to April 14^th, 2005. We find that improvements of the overall estimation are achieved when asymmetric GARCH models are used with student-t distribution and generalized error distribution. Moreover, it is found that TARCH and GARCH models give better forecasting performance than EGARCH and APARCH models. In forecasting performance, the model under normal distribution gives more accurate forecasting performance than non-normal densities and generalized error distributions clearly outperform the student-t densities in case of SSE.
文摘A suitable statistical model has been explored for the investors as well as the researchers to resolve the future estimation of share volume by using daily stock volume data from Dhaka Stock Exchange (DSE). The daily volume data from the June 1, 2004 to April 19, 2010 were retrieved from DSE website as a secondary data source. The Maximum Likelihood---Autoregressive Conditional Heteroskedasticity (ARCH) (Marquardt) method has been applied to construct the models for the stock volume data of DSE by using statistical package software E-Views of verson-5. First of all, an "Auto Regressive Integrated Moving Average (ARIMA) model" was fitted and observed that heteroscedastic volatilities were still present there. To eliminate this dilemma, ARCH class of volatility models has been used and finally the ARIMA with EGARCH model has been explored. Findings of this study have recognized that ARIMA with EGARCH model implies low mean square error, low mean absolute error, low bias proportion, and low variance proportion for share volume data with comparing to other models. Hence, the modelling concept established in this study would be a decisive study for the investors as well as the researchers.
文摘Since the establishment of financial models for risk prediction,the measurement of volatility at risky market has improved,and its significance has also grown.For high-frequency financial data,the degree of investment risk,which has always been the focus of attention,is measured by the variance of residual sequence obtained following model regression.By integrating the long short-term memory(LSTM)model with multiple generalized autoregressive conditional heteroscedasticity(GARCH)models,a new hybrid LSTM model is used to predict stock price volatility.In this paper,three GARCH models are used,and the model that can best fit the data is determined.
文摘The financial market is the core of national economic development,and stocks play an important role in the financial market.Analyzing stock prices has become the focus of investors,analysts,and people in related fields.This paper evaluates the volatility of Apple Inc.(AAPL)returns using five generalized autoregressive conditional heteroskedasticity(GARCH)models:sGARCH with constant mean,GARCH with sstd,GJR-GARCH,AR(1)GJR-GARCH,and GJR-GARCH in mean.The distribution of AAPL’s closing price and earnings data was analyzed,and skewed student t-distribution(sstd)and normal distribution(norm)were used to further compare the data distribution of the five models and capture the shape,skewness,and loglikelihood in Model 4-AR(1)GJR-GARCH.Through further analysis,the results showed that Model 4,AR(1)GJR-GARCH,is the optimal model to describe the volatility of the return series of AAPL.The analysis of the research process is both,a process of exploration and reflection.By analyzing the stock price of AAPL,we reflect on the shortcomings of previous analysis methods,clarify the purpose of the experiment,and identify the optimal analysis model.
基金support from National Natural Science Foundation of China(Nos.71774051,72243003)National Social Science Fund of China(No.22AZD128)the seminar participants in Center for Resource and Environmental Management,Hunan University,China.
文摘Forecasting returns for the Artificial Intelligence and Robotics Index is of great significance for financial market stability,and the development of the artificial intelligence industry.To provide investors with a more reliable reference in terms of artificial intelligence index investment,this paper selects the NASDAQ CTA Artificial Intelligence and Robotics(AIRO)Index as the research target,and proposes innovative hybrid methods to forecast returns by considering its multiple structural characteristics.Specifically,this paper uses the ensemble empirical mode decomposition(EEMD)method and the modified iterative cumulative sum of squares(ICSS)algorithm to decompose the index returns and identify the structural breakpoints.Furthermore,it combines the least-square support vector machine approach with the particle swarm optimization method(PSO-LSSVM)and the generalized autoregressive conditional heteroskedasticity(GARCH)type models to construct innovative hybrid forecasting methods.On the one hand,the empirical results indicate that the AIRO index returns have complex structural characteristics,and present time-varying and nonlinear characteristics with high complexity and mutability;on the other hand,the newly proposed hybrid forecasting method(i.e.,the EEMD-PSO-LSSVM-ICSS-GARCH models)which considers these complex structural characteristics,can yield the optimal forecasting performance for the AIRO index returns.
基金Project(20090162120086) supported by Research Fund for the Doctoral Program of Higher Education of ChinaProject(10YJCZH123) supported by Humanity and Social Science Foundation of Ministry of Education of China+2 种基金Project(12JJ4077) supported by the National Natural Science Foundation of Hunan Province of ChinaProject(2009ZK3053) supported by Soft Science Research Project of Hunan Province of ChinaProject supported by the Freedom Explore Program of Central South University,China
文摘By using GARCH(1,1)-M and EGARCH(1,1)-M models, the relationships among funds speculation transaction, arbitrage transaction and the fluctuation of international copper future price were studied. The news impact curve of copper future price fluctuation respectively introduced funds speculation position and arbitrage position was given, and the result is consistent with the empirical study conclusion. The results show that investment funds are not the factor that causes copper future price fluctuation, but can reduce the copper future price fluctuation; the copper future price fluctuation is more sensitive to negative information, and ftmd speculative positions can reduce asymmetric effect of copper price fluctuation, while fimds arbitrage position influences less.
文摘Natural ventilation is driven by either buoyancy forces or wind pressure forces or their combinations that inherit stochastic variation into ventilation rates. Since the ventilation rate is a nonlinear function of multiple variable factors including wind speed, wind direction, internal heat source and building structural thermal mass, the conventional methods for quantifying ventilation rate simply using dominant wind direction and average wind speed may not accurately describe the characteristic performance of natural ventilation. From a new point of view, the natural ventilation performance of a single room building under fluctuating wind speed condition using the Monte-Carlo simulation approach was investigated by incorporating building facade thermal mass effect. Given a same hourly turbulence intensity distribution, the wind speeds with 1 rain frequency fluctuations were generated using a stochastic model, the modified GARCH model. Comparisons of natural ventilation profiles, effective ventilation rates, and air conditioning electricity use for a three-month period show statistically significant differences (for 80% confidence interval) between the new calculations and the traditional methods based on hourly average wind speed.
文摘This paper uses a Value at Risk (VaR) approach to evaluate a country financial vulnerability, by analyzing the risk exposure of its Central Bank, as if their assets are subject to market risk. The Brazilian currency exchange swaps contracts (USS/Brazilian Reais) are submitted to a delta-normal VaR method, in order to evaluate the market risk of each swaps series, by modeling the variance of the daily returns, from August 1999 to January 2003. All daily returns series exhibited heteroscedasticity in the conditional variance and sudden changes in the unconditional variance. The points of changes of the unconditional variance were determined through the Iterative Cumulative Sum of Squares (ICSS) algorithm, and the conditional variance was modeled with Markov-Switching-Generalized Autoregressive Conditional Heteroscedasticity (SWGARCH) in order to capture heteroscedasticity and regime change. The results lead to two main conclusions: First, a VaR model must incorporate heteroscedasticity and regime switching in order to describe the variance of the tested series, submitted to brisk changes of economic and political scenarios. Second, a volatility-based VaR do not necessarily generate forward-looking indicators, but rather coincident indicators of possible financial vulnerabilities. The future research will evolve towards evaluating the effects of the Basel III recommendations as if they could be applied to this crisis period.
文摘Gold is always a precious metal for many hundred years. Semi flexible gold demand and supply chain determines international gold prices in the long term. USA is ranked the world’s largest gold producer. This study mainly aims to investigate the dynamic factors which affect the price of gold and determine the essential macro-economic variable that has the most important role during the process. This paper examines USA over 13 years applying a formal test for time series, which interrogate cointegration relationships, what is the affiliation between gold price and other factors, which are explained in detail below. The present study has used the monthly data from January, 2003 to June, 2016. Databases are provided by the Federal Reserve, the central bank of the United States, and United States Energy Information Administration. Data analysis was performed with software package EViews 8. Through the time series, an analysis has been carried out on Dow Jones Index, the US exchange rate, silver price, interest rate, oil price and inflation rate which are thought to influence the price of gold in the most significant way. The data analysis includes the determination of the conditional heteroscedastic model to estimate volatility. Therefore, the best fitting model to the data set, which is the exponential GARCH model, is preferred. In accordance with the results of the empirical analyses in the USA, the highest negative correlation is found between gold prices and US exchange rate. Secondly, a positive correlation is found among gold prices, silver prices, and oil prices. Another point which takes attention as a result of the study is that economic and political structural breaks weighed heavily, traders and hedgers from all over the world were able to drive prices up to incredible highs. The added valueof our study arises from the inclusion in the analysis of macro economic variables, which has proved to have crucial relevance for the price of gold in the context of the recent economic structure.
文摘Margin rules are very important rules in futures market. This paper provides a new Value-at-Risk (VaR) approach which uses GARCH model to set margin levels. The new approach overcomes the limitation of the hypothesis of normal distribution in traditional methods and improves the estimation precision. We use the data of metal futures in China's Shanghai Futures Exchange (SHFE) to have an empirical study.
基金supported by the National Hi-Tech Research and Development Program of China ("863" Project) (Grant No. 2012BAB02B04)
文摘Uncertainty analysis and risk analysis are two important areas of modern water resource management,in which accurate variance estimation is required.The traditional runoff model is established under the assumption that the variance is a constant or it changes with the seasons.However,hydrological processes in the real world are often heteroscedastic,which can be tested by McLeod-Li test and Engle Lagrange multiplier test.In such cases,the GARCH model of hydrological processes is established in this article.First,the seasonal factors in the sequence are removed.Second,the traditional ARMA model is established.Then,the GARCH model is used to correct the residual.At last,the daily runoff data in 1949-2001 of Yichang Hydrological Station is taken to be an example.The result shows that compared to the traditional ARMA model,the GARCH model has the ability to predict more accurate confidence intervals under the same confidence level.
基金supported by the National Natural Science Foundation of China under Grant Nos.71171012and 70901019Humanity and Social Science Foundation of Ministry of Education of China under Grant No.14YJA790075
文摘This paper investigates the mean-reversion and volatile of credit spread time series by using regression and time series analysis in Chinese bond market. Then the Longstaff-Schwartz model and GARCH model are applied to price credit spread put option. The authors compare the features of these two models by employing daily bond prices of government bonds and corporate bonds for the period 2010–2012 in Chinese bond market. The proposed results show that the higher the credit ratings of the corporate bonds are, the lower the prices of the credit spread options are.
基金funded by National Natural Science Foundation of China (51577025).
文摘Wind power forecasting is of great significance to the safety, reliability and stability of power grid. In this study, the GARCH type models are employed to explore the asymmetric features of wind power time series and improved forecasting precision. Benchmark Symmetric Curve (BSC) and Asymmetric Curve Index (ACI) are proposed as new asymmetric volatility analytical tool, and several generalized applications are presented. In the case study, the utility of the GARCH-type models in depicting time-varying volatility of wind power time series is demonstrated with the asymmetry effect, verified by the asymmetric parameter estimation. With benefit of the enhanced News Impact Curve (NIC) analysis, the responses in volatility to the magnitude and the sign of shocks are emphasized. The results are all confirmed to be consistent despite varied model specifications. The case study verifies that the models considering the asymmetric effect of volatility benefit the wind power forecasting performance.