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Probability Distribution of China Aviation Network Average Degree of Edge Vertices and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Zhang Chunyue Liang Yanping 《Journal of Traffic and Transportation Engineering》 2024年第2期51-62,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of average degree of edge vertices of China aviation network w... In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of average degree of edge vertices of China aviation network were studied based on the statistics data of China civil aviation network in 1988, 1994, 2001, 2008 and 2015. According to the theory and method of complex network, the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network. Based on the statistical data, the average degrees of edge vertices in China aviation network in 1988, 1994, 2001, 2008 and 2015 were calculated. Using the probability statistical analysis method and regression analysis approach, it was found that the average degree of edge vertices had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network average degree of edge vertices normal distribution linear evolution trace
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Damage constitutive model for strain-softening rock based on normal distribution and its parameter determination 被引量:14
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作者 曹文贵 李翔 赵衡 《Journal of Central South University of Technology》 EI 2007年第5期719-724,共6页
Firstly, using the damage model for rock based on Lemaitre hypothesis about strain equivalence, a new technique for measuring strength of rock micro-cells by adopting the Mohr-Coulomb criterion was developed, and a st... Firstly, using the damage model for rock based on Lemaitre hypothesis about strain equivalence, a new technique for measuring strength of rock micro-cells by adopting the Mohr-Coulomb criterion was developed, and a statistical damage evolution equation was established based on the property that strength of micro-cells is consistent with normal distribution function, through discussing the characteristics of random distributions for strength of micro-cells, then a statistical damage constitutive model that can simulate the full process of rock strain softening under specific confining pressure was set up. Secondly, a new method to determine the model parameters which can be applied to the situations under different confining pressures was proposed, by deeply studying the relations between the model parameters and characteristic parameters of the full stress-strain curve under different confining pressures. Therefore, a unified statistical damage constitutive model for rock softening which can reflect the effect of different confining pressures was set up. This model makes the physical property of model parameters explicit, contains only conventional mechanical parameters, and leads its application more convenient. Finally, the rationality of this model and its parameters-determining method were identified via comparative analyses between theoretical and experimental curves. 展开更多
关键词 constitutive model ROCK DAMAGE strain softening normal distribution
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Omni-Directional Distribution Patterns of Montane Coniferous Forest in the Helan Mountains of China 被引量:5
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作者 PANG Yu ZHANG Bai-ping +3 位作者 ZHAO Fang YAO Yong-hui ZHANG Shuo QI Wen-wen 《Journal of Mountain Science》 SCIE CSCD 2013年第5期724-733,共10页
Slope aspect has significant effect on the development and distribution of montane forest, especially in arid and semiarid regions. This paper, using SPOT5 images and 1:5o,ooo DEM, digitally extracts and analyzes the... Slope aspect has significant effect on the development and distribution of montane forest, especially in arid and semiarid regions. This paper, using SPOT5 images and 1:5o,ooo DEM, digitally extracts and analyzes the spatial information of montane coniferous forest (mainly Qinghai spruce), and thereby explores how the upper and lower limits and the altitudinal range of coniferous forest vary and how the area of coniferous forest is related with annual insolation with all aspects in the Helan Mountains. The results show that: 1) In the eastern flank, the lower limit of coniferous forest is between 1,6oo m and a,ooo m a.s.l., and the upper limit between 2,800 m and 3,ooo m a.s.1.; in the western flank, the lower limit of coniferous forest is between a,ooo m and 2,300 m a.s.l., and the upper limit between 9,80o m and 3,1oo m a.s.1.2) The altitudinal ranges of coniferous forest are 8o6-1,435 m, 438-1,14o m for eastern flank and western flank, respectively. 3) The area of coniferous forest takes on a normal distribution with aspect, and it has a close relationship with annual insolation. This distribution model developed in this paper quantitatively reveals the significant effect of slope aspect on the distribution of coniferous forest in arid and semi-arid land. 展开更多
关键词 Arid region Helan Mountains Qinghaispruce (Picea crassifolia) Aspect effect Coniferousforest Normal distribution
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Minimax Estimation of the Function of Parameters in Normal Distribution 被引量:2
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作者 MENG Hong-ling KANG Jin-xuan ZHANG Kai-guang 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第2期242-245,共4页
The estimation of the functionθ=exp{αμ+bσ2} of parameters (μ,σ2) in normal distribution N(μ,σ2) is discussed. And when the prior distributions ofμandσ2 are independent, under the loss function L(θ,δ)=(θ-1... The estimation of the functionθ=exp{αμ+bσ2} of parameters (μ,σ2) in normal distribution N(μ,σ2) is discussed. And when the prior distributions ofμandσ2 are independent, under the loss function L(θ,δ)=(θ-1×δ-1)2, the Bayesian estimation and the existence and computing method on minimax estimation are deeply discussed. 展开更多
关键词 normal distribution logarithmic normal distribution prior distribution Bayesian estimation minimax estimation
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Joint modelling of location and scale parameters of the skew-normal distribution 被引量:2
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作者 LI Hui-qiong WU Liu-cang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2014年第3期265-272,共8页
Joint location and scale models of the skew-normal distribution provide useful ex- tension for joint mean and variance models of the normal distribution when the data set under consideration involves asymmetric outcom... Joint location and scale models of the skew-normal distribution provide useful ex- tension for joint mean and variance models of the normal distribution when the data set under consideration involves asymmetric outcomes. This paper focuses on the maximum likelihood estimation of joint location and scale models of the skew-normal distribution. The proposed procedure can simultaneously estimate parameters in the location model and the scale model. Simulation studies and a real example are used to illustrate the proposed methodologies. 展开更多
关键词 joint mean and variance models of the normal distribution joint location and scale models ofthe skew-normal distribution maximum likelihood estimators skew-normal distribution.
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A new approach to retrieve leaf normal distribution using terrestrial laser scanners 被引量:1
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作者 Shengye Jin Masayuki Tamura Junichi Susaki 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第3期631-638,共8页
Leaf normal distribution is an important structural characteristic of the forest canopy. Although terrestrial laser scanners(TLS) have potential for estimating canopy structural parameters, distinguishing between le... Leaf normal distribution is an important structural characteristic of the forest canopy. Although terrestrial laser scanners(TLS) have potential for estimating canopy structural parameters, distinguishing between leaves and nonphotosynthetic structures to retrieve the leaf normal has been challenging. We used here an approach to accurately retrieve the leaf normals of camphorwood(Cinnamomum camphora) using TLS point cloud data.First, nonphotosynthetic structures were filtered by using the curvature threshold of each point. Then, the point cloud data were segmented by a voxel method and clustered by a Gaussian mixture model in each voxel. Finally, the normal vector of each cluster was computed by principal component analysis to obtain the leaf normal distribution. We collected leaf inclination angles and estimated the distribution, which we compared with the retrieved leaf normal distribution. The correlation coefficient between measurements and obtained results was 0.96, indicating a good coincidence. 展开更多
关键词 Leaf normal distribution Leaf inclinationangle Terrestrial laser scanner Point cloud data Curvature - Clustering
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The Limitations of Polygenic Hypothesis and Theorizing about Dual Multiple Factors and Three Normal Distributions 被引量:2
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作者 Tingzhen Zhang Xiaoming Jia Zhao Xu 《Applied Mathematics》 2016年第9期912-919,共8页
The original data of Nilsson-Ehle experiment in wheat were analyzed with existent genetic knowledge. It indicated that the core of polygenic hypothesis from this experiment was that a character similarity produced by ... The original data of Nilsson-Ehle experiment in wheat were analyzed with existent genetic knowledge. It indicated that the core of polygenic hypothesis from this experiment was that a character similarity produced by additive effect of multiple genes was the basis of continuous variation. Its precondition was for effective genes to have equal effect, to show merodominance and binomial distribution  and  to inherit independently. In fact, quantitative characters were determined by many genes with different property, effect and behavior. So it was difficult to solve all problems of continuous variation by the aid of polygenic hypothesis. The researchers should seek new ways. With Mendelian group as research object and by means of Lyapunov central limit theorem it was proved that both genotypic value G and the environmental effect in a niche E were subordinated to the normal distribution and respectively. According to additivity of the normal distribution the phenotype P = G + E also obeyed the normal distribution P = G + E ~  and quantitative characters showed continuous variation, whether or not the linkage was presented, whether or not every gene effect was equal, whether or not there were dominance and what kind of dominance between alleles. Moreover it was discussed that the quantitative characters in self-fertilized organism and clone were submitted to the normal distribution and presented continuous variation too. 展开更多
关键词 Inheritance of Quantitative Character Mendelian Population Central Limit Theorem Genotypic Value G Environmental Effect E Phenotype P Normal distribution
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An improved model of partition curve based on accumulation normal distribution function 被引量:2
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作者 Sun Wei Chen Jianzhong +1 位作者 Shen Lijuan Li Yonggai 《International Journal of Mining Science and Technology》 SCIE EI 2013年第3期375-380,共6页
Extensive studies based on partition curve of gravity separation have been investigated. All created models are merely used to simulate density distribution at the same size fraction. However, they cannot be used to p... Extensive studies based on partition curve of gravity separation have been investigated. All created models are merely used to simulate density distribution at the same size fraction. However, they cannot be used to predictive distribution of materials depending on compound feature of density and size. According to this situation, an improved model of partition curve based on accumulation normal distribution, which was distinguished from conventional model of accumulation normal distribution for partition curve, was proposed in this paper. It could simulate density distribution at different size fractions by using the density-size compound index and conflating the partition curves at different size fractions as one partition curve. The feasibility of three compound indexes, including mass index, settlement index and transformation index, were investigated. Specific forms of the improved model were also proposed. It is found that transformation index leads to the best fitting results, while the fitting error is only 1.75 according to the fitting partition curve. 展开更多
关键词 Coal preparation Mathematical model Partition curve Accumulation normal distribution model
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About the Mean Difference of the Inverse Normal Distribution 被引量:1
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作者 Giovanni Girone Angela Maria D’Uggento 《Applied Mathematics》 2016年第14期1504-1509,共7页
The calculation of the mean difference for the inverse normal distribution can be obtained by a transformation of variable or a hard integration by parts. This paper shows a simpler formula of the mean difference of t... The calculation of the mean difference for the inverse normal distribution can be obtained by a transformation of variable or a hard integration by parts. This paper shows a simpler formula of the mean difference of the inverse normal distribution that highlights the role of the two parameters on the mean difference of the model. It makes it easier to study the relation of the mean difference with the other indexes of variability for the inverse normal distribution. 展开更多
关键词 Mean Difference Inverse Normal distribution
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Modeling Liver Cancer and Leukemia Data Using Arcsine-Gaussian Distribution
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作者 Farouq Mohammad A.Alam Sharifah Alrajhi +1 位作者 Mazen Nassar Ahmed Z.Afify 《Computers, Materials & Continua》 SCIE EI 2021年第5期2185-2202,共18页
The main objective of this paper is to discuss a general family of distributions generated from the symmetrical arcsine distribution.The considered family includes various asymmetrical and symmetrical probability dist... The main objective of this paper is to discuss a general family of distributions generated from the symmetrical arcsine distribution.The considered family includes various asymmetrical and symmetrical probability distributions as special cases.A particular case of a symmetrical probability distribution from this family is the Arcsine–Gaussian distribution.Key statistical properties of this distribution including quantile,mean residual life,order statistics and moments are derived.The Arcsine–Gaussian parameters are estimated using two classical estimation methods called moments and maximum likelihood methods.A simulation study which provides asymptotic distribution of all considered point estimators,90%and 95%asymptotic confidence intervals are performed to examine the estimation efficiency of the considered methods numerically.The simulation results show that both biases and variances of the estimators tend to zero as the sample size increases,i.e.,the estimators are asymptotically consistent.Also,when the sample size increases the coverage probabilities of the confidence intervals increase to the nominal levels,while the corresponding length decrease and approach zero.Two real data sets from the medicine filed are used to illustrate the flexibility of the Arcsine–Gaussian distribution as compared with the normal,logistic,and Cauchy models.The proposed distribution is very versatile to fit real applications and can be used as a good alternative to the traditional gaussian distribution. 展开更多
关键词 Liver cancer data leukemia data normal distribution moments estimation maximum likelihood estimation
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Medical Feature Selection Approach Based on Generalized Normal Distribution Algorithm
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作者 Mohamed Abdel-Basset Reda Mohamed +3 位作者 Ripon K.Chakrabortty Michael J.Ryan Yunyoung Nam Mohamed Abouhawwash 《Computers, Materials & Continua》 SCIE EI 2021年第12期2883-2901,共19页
This paper proposes a new pre-processing technique to separate the most effective features from those that might deteriorate the performance of the machine learning classifiers in terms of computational costs and clas... This paper proposes a new pre-processing technique to separate the most effective features from those that might deteriorate the performance of the machine learning classifiers in terms of computational costs and classification accuracy because of their irrelevance,redundancy,or less information;this pre-processing process is often known as feature selection.This technique is based on adopting a new optimization algorithm known as generalized normal distribution optimization(GNDO)supported by the conversion of the normal distribution to a binary one using the arctangent transfer function to convert the continuous values into binary values.Further,a novel restarting strategy(RS)is proposed to preserve the diversity among the solutions within the population by identifying the solutions that exceed a specific distance from the best-so-far and replace them with the others created using an effective updating scheme.This strategy is integrated with GNDO to propose another binary variant having a high ability to preserve the diversity of the solutions for avoiding becoming stuck in local minima and accelerating convergence,namely improved GNDO(IGNDO).The proposed GNDO and IGNDO algorithms are extensively compared with seven state-of-the-art algorithms to verify their performance on thirteen medical instances taken from the UCI repository.IGNDO is shown to be superior in terms of fitness value and classification accuracy and competitive with the others in terms of the selected features.Since the principal goal in solving the FS problem is to find the appropriate subset of features that maximize classification accuracy,IGNDO is considered the best. 展开更多
关键词 Generalized normal distribution optimization feature selection transfer function novel restarting strategy UCI repository
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Single-peak distribution model of particulate size for welding aerosols
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作者 施雨湘 李爱农 《China Welding》 EI CAS 2003年第1期45-49,共5页
A large number of particulate size distributions of welding aerosols are measured by means of DMPS method, several distribution types are presented. Among them the single peak distribution is the basic composing unit... A large number of particulate size distributions of welding aerosols are measured by means of DMPS method, several distribution types are presented. Among them the single peak distribution is the basic composing unit of particulate size. The research on the mathematic models and distributions functions shows that the single peak distribution features the log normal distribution. The diagram estimating method (DEM) is a concise approach to dealing with distribution types, obtaining distribution functions for the particulate sizes of welding aerosols. It proves that the distribution function of particulate size possesses the extending property, being from quantity distribution to volume, as well as high order moment distributions, with K S method verifying the application of single peak distribution and of DEM. 展开更多
关键词 welding aerosols distribution function log normal distribution diagram estimating method (DEM) welding fume
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Asymptotic Distribution of a Kind of Dirichlet Distribution
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作者 CHEN FEI SONG LI-XIN 《Communications in Mathematical Research》 CSCD 2010年第1期17-26,共10页
The Dirichlet distribution that we are concerned with in this paper is very special, in which all parameters are different from each other. We prove that the asymptotic distribution of this kind of Dirichlet distribut... The Dirichlet distribution that we are concerned with in this paper is very special, in which all parameters are different from each other. We prove that the asymptotic distribution of this kind of Dirichlet distributions is a normal distribution by using the central limit theorem and Slutsky theorem. 展开更多
关键词 Dirichlet distribution asymptotic distribution normal distribution
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Constant-Step Stress Accelerated Life Test of VFD under Logarithmic Normal Distribution Case
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作者 张建平 谢秀中 赵科仁 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第1期14-17,共4页
In order to solve the life problem of vacuum fluorescent display (VFD) within shorter time, and reduce the life prediction cost, a constant-step stress accelerated life test was performed with its cathode temperature ... In order to solve the life problem of vacuum fluorescent display (VFD) within shorter time, and reduce the life prediction cost, a constant-step stress accelerated life test was performed with its cathode temperature increased. Statistical analysis was done by applying logarithmic normal distribution for describing the life, and least square method (LSM) for estimating logarithmic normal parameters. Self-designed special software was used to predict the VFD life. It is verified by numerical results that the VFD life follows logarithmic normal distribution, and that the life-stress relationship satisfies linear Arrhenius equation completely. The accurate calculation of the key parameters enables the rapid estimation of VFD life. 展开更多
关键词 vacuum fluorescent display accelerated life test logarithmic normal distribution
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Coordinate-Momentum Intermediate Representation and Marginal Distributions of Quantum Mechanical Bivariate Normal Distribution
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作者 FAN Hong-Yi LOU Sen-Yue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第3期613-616,共4页
We introduce bivariate normal distribution operator for state vector [ψ) and find that its marginal distribution leads to one-dimensional normal distribution corresponding to the measurement probability |λ,v〈x|... We introduce bivariate normal distribution operator for state vector [ψ) and find that its marginal distribution leads to one-dimensional normal distribution corresponding to the measurement probability |λ,v〈x|.ψ〉|^2, where |x〉λ,v is the coordinate-momentum intermediate representation. As a by-product, the one-dimensional normal distribution in statistics can be explained as a Radon transform of two-dimensional Gaussian function. 展开更多
关键词 coordinate-momentum intermediate representation bivariate normal distribution
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Generalized Wigner Operator and Bivariate Normal Distribution in p-q Phase Space
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作者 FAN Hong-Yi WANG Tong-Tong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1299-1302,共4页
We introduce a kind of generalized Wigner operator,whose normally ordered form can lead to the bivariatenormal distribution in p-q phase space.While this bivariate normal distribution corresponds to the pure vacuum st... We introduce a kind of generalized Wigner operator,whose normally ordered form can lead to the bivariatenormal distribution in p-q phase space.While this bivariate normal distribution corresponds to the pure vacuum state inthe generalized Wigner function phase space,it corresponds to a mixed state in the usual Wigner function phase space. 展开更多
关键词 bivariate normal distribution generalized Wigner operator
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LOGARITHMIC GAUSS NORMAL DISTRIBUTION OF MICROLATEX PARTICLE OF EMULSION EXPLOSIVES
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作者 徐国财 《Journal of Coal Science & Engineering(China)》 1998年第2期68-72,共5页
Microlatex particles of emulsion explosives determined by microphotography were studied with the law of logarithmic Gauss normal distribution, and results obtained showed that the microlatex particle just possessed th... Microlatex particles of emulsion explosives determined by microphotography were studied with the law of logarithmic Gauss normal distribution, and results obtained showed that the microlatex particle just possessed the law of logarithmic Gauss normal distribution. The particle diameter in statistical average value, such as DNL, DNS, DLS, DSV and DVM was calculated through the diagram of logarithmic Gauss normal distribution of microlatex particles of emulsion explosives, so was SW. 展开更多
关键词 emulsion explosive microlatex particle logarithmic Gauss normal distribution
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Mean Difference of Truncated Normal Distribution
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作者 Giovanni Girone Antonella Massari +1 位作者 Fabio Manca Claudia Marin 《Applied Mathematics》 2020年第11期1162-1166,共5页
The purpose of this paper is to broaden the knowledge of mean difference and, in particular, of an important distribution model known as truncated normal distribution, which is widely used in applied sciences and econ... The purpose of this paper is to broaden the knowledge of mean difference and, in particular, of an important distribution model known as truncated normal distribution, which is widely used in applied sciences and economics. In this work, we obtained the general formula of mean difference, which is not yet reported in literature, for the aforementioned distribution model and also for particular truncated cases. 展开更多
关键词 Mean Difference Truncated Normal distribution Variability Indexes Economic Sciences
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Some Necessary and Sufficient Condition of Multivariate Random Variable Satisfy Normal Distribution
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作者 伍俊良 秦志仁 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第1期39-41,共3页
In this paper,we extended some results of article[1],obtain some sufficient and necessary condition which multivariate random variable satisfy normal distribution.
关键词 multivariate random variable normal distribution:sufficient and necessary condition
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Comparative Research on the Stock Return Distributional Models
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作者 ZHANG Qiang 《Journal of Modern Accounting and Auditing》 2007年第2期35-40,共6页
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
关键词 stock return distribution mixture normal distribution mixed diffusion-jump model GARCH models
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