The relation between the occurrence of strong earthquakes and the tomographic velocity structure in North China is quantitatively analyzed by using the AIC analysis method for categorical data. The results indicate th...The relation between the occurrence of strong earthquakes and the tomographic velocity structure in North China is quantitatively analyzed by using the AIC analysis method for categorical data. The results indicate that the areas of low P wave velocity in the lower crust and the top of upper mantle and areas of high S wave horizontal gradient in the upper and lower crust are correlated with earthquakes of magnitude greater than 5～6. The correlation may be related to the geodynamics of Cenozoic thinning of the lithosphere and upwelling of mantle materials. The lateral inhomogeneous zones in crustal structure and thermal state are prone to occur strong earthquakes.展开更多
This article introduces a resampling procedure called the truncated geometric bootstrap method for stationary time series process. This procedure is based on resampling blocks of random length, where the length of eac...This article introduces a resampling procedure called the truncated geometric bootstrap method for stationary time series process. This procedure is based on resampling blocks of random length, where the length of each blocks has a truncated geometric distribution and capable of determining the probability p and number of block b. Special attention is given to problems with dependent data, and application with real data was carried out. Autoregressive model was fitted and the choice of order determined by Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). The normality test was carried out on the residual variance of the fitted model using Jargue-Bera statistics, and the best model was determined based on root mean square error of the forecasting values. The bootstrap method gives a better and a reliable model for predictive purposes. All the models for the different block sizes are good. They preserve and maintain stationary data structure of the process and are reliable for predictive purposes, confirming the efficiency of the proposed method.展开更多
文摘The relation between the occurrence of strong earthquakes and the tomographic velocity structure in North China is quantitatively analyzed by using the AIC analysis method for categorical data. The results indicate that the areas of low P wave velocity in the lower crust and the top of upper mantle and areas of high S wave horizontal gradient in the upper and lower crust are correlated with earthquakes of magnitude greater than 5～6. The correlation may be related to the geodynamics of Cenozoic thinning of the lithosphere and upwelling of mantle materials. The lateral inhomogeneous zones in crustal structure and thermal state are prone to occur strong earthquakes.
文摘This article introduces a resampling procedure called the truncated geometric bootstrap method for stationary time series process. This procedure is based on resampling blocks of random length, where the length of each blocks has a truncated geometric distribution and capable of determining the probability p and number of block b. Special attention is given to problems with dependent data, and application with real data was carried out. Autoregressive model was fitted and the choice of order determined by Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC). The normality test was carried out on the residual variance of the fitted model using Jargue-Bera statistics, and the best model was determined based on root mean square error of the forecasting values. The bootstrap method gives a better and a reliable model for predictive purposes. All the models for the different block sizes are good. They preserve and maintain stationary data structure of the process and are reliable for predictive purposes, confirming the efficiency of the proposed method.
