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Non-negative least squares variance component estimation of mixed additive and multiplicative random error model
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作者 Hao Xiao Leyang Wang 《Geodesy and Geodynamics》 2025年第5期617-623,共7页
In the variance component estimation(VCE)of geodetic data,the problem of negative VCE is likely to occur.In the ordinary additive error model,there have been related studies to solve the problem of negative variance c... In the variance component estimation(VCE)of geodetic data,the problem of negative VCE is likely to occur.In the ordinary additive error model,there have been related studies to solve the problem of negative variance components.However,there is still no related research in the mixed additive and multiplicative random error model(MAMREM).Based on the MAMREM,this paper applies the nonnegative least squares variance component estimation(NNLS-VCE)algorithm to this model.The correlation formula and iterative algorithm of NNLS-VCE for MAMREM are derived.The problem of negative variance in VCE for MAMREM is solved.This paper uses the digital simulation example and the Digital Terrain Mode(DTM)to prove the proposed algorithm's validity.The experimental results demonstrated that the proposed algorithm can effectively correct the VCE in MAMREM when there is a negative VCE. 展开更多
关键词 Mixed additive and multiplicative random error model Stochastic model Non-negative least squares variance component estimation
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Seismic attenuation relationship with homogeneous and heterogeneous prediction-error variance models 被引量:4
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作者 He-Qing Mu Rong-Rong Xu Ka-Veng Yuen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2014年第1期1-11,共11页
Peak ground acceleration(PGA) estimation is an important task in earthquake engineering practice.One of the most well-known models is the Boore-Joyner-Fumal formula,which estimates the PGA using the moment magnitude,t... Peak ground acceleration(PGA) estimation is an important task in earthquake engineering practice.One of the most well-known models is the Boore-Joyner-Fumal formula,which estimates the PGA using the moment magnitude,the site-to-fault distance and the site foundation properties.In the present study,the complexity for this formula and the homogeneity assumption for the prediction-error variance are investigated and an effi ciency-robustness balanced formula is proposed.For this purpose,a reduced-order Monte Carlo simulation algorithm for Bayesian model class selection is presented to obtain the most suitable predictive formula and prediction-error model for the seismic attenuation relationship.In this approach,each model class(a predictive formula with a prediction-error model) is evaluated according to its plausibility given the data.The one with the highest plausibility is robust since it possesses the optimal balance between the data fi tting capability and the sensitivity to noise.A database of strong ground motion records in the Tangshan region of China is obtained from the China Earthquake Data Center for the analysis.The optimal predictive formula is proposed based on this database.It is shown that the proposed formula with heterogeneous prediction-error variance is much simpler than the attenuation model suggested by Boore,Joyner and Fumal(1993). 展开更多
关键词 Bayesian inference Boore-Joyner-Fumal formula heterogeneity variance input-dependent variance model class selection peak ground acceleration seismic attenuation
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EMPIRICAL BAYES TEST PROBLEMS OF VARIANCE COMPONENTS IN RANDOM EFFECTS MODEL 被引量:3
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作者 韦来生 张伟平 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期274-282,共9页
Bayes decision rule of variance components for one-way random effects model is derived and empirical Bayes (EB) decision rules are constructed by kernel estimation method. Under suitable conditions, it is shown that t... Bayes decision rule of variance components for one-way random effects model is derived and empirical Bayes (EB) decision rules are constructed by kernel estimation method. Under suitable conditions, it is shown that the proposed EB decision rules are asymptotically optimal with convergence rates near O(n-1/2). Finally, an example concerning the main result is given. 展开更多
关键词 Empirical Bayes test variance components random effects model convergence rates
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A discrete-event model to simulate the effect of truck bunching due to payload variance on cycle time, hauled mine materials and fuel consumption 被引量:2
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作者 A.Soofastaei S.M.Aminossadati +1 位作者 M.S.Kizil P.Knights 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期745-752,共8页
Data collected from truck payload management systems at various surface mines shows that the payload variance is significant and must be considered in analysing the mine productivity,energy consumption,greenhouse gas ... Data collected from truck payload management systems at various surface mines shows that the payload variance is significant and must be considered in analysing the mine productivity,energy consumption,greenhouse gas emissions and associated cost.Payload variance causes significant differences in gross vehicle weights.Heavily loaded trucks travel slower up ramps than lightly loaded trucks.Faster trucks are slowed by the presence of slower trucks,resulting in‘bunching’,production losses and increasing fuel consumptions.This paper simulates the truck bunching phenomena in large surface mines to improve truck and shovel systems’efficiency and minimise fuel consumption.The study concentrated on completing a practical simulation model based on a discrete event method which is most commonly used in this field of research in other industries.The simulation model has been validated by a dataset collected from a large surface mine in Arizona state,USA.The results have shown that there is a good agreement between the actual and estimated values of investigated parameters. 展开更多
关键词 Discrete-event model Simulation Truck bunching Payload variance Cycle time Fuel consumption
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Nonlinear total least-squares variance component estimation for GM(1,1)model 被引量:3
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作者 Leyang Wang Jianqiang Sun Qiwen Wu 《Geodesy and Geodynamics》 CSCD 2021年第3期211-217,共7页
The solution of the grey model(GM(1,1)model)generally involves equal-precision observations,and the(co)variance matrix is established from the prior information.However,the data are generally available with unequal-pr... The solution of the grey model(GM(1,1)model)generally involves equal-precision observations,and the(co)variance matrix is established from the prior information.However,the data are generally available with unequal-precision measurements in reality.To deal with the errors of all observations for GM(1,1)model with errors-in-variables(EIV)structure,we exploit the total least-squares(TLS)algorithm to estimate the parameters of GM(1,1)model in this paper.Ignoring that the effect of the improper prior stochastic model and the homologous observations may degrade the accuracy of parameter estimation,we further present a nonlinear total least-squares variance component estimation approach for GM(1,1)model,which resorts to the minimum norm quadratic unbiased estimation(MINQUE).The practical and simulative experiments indicate that the presented approach has significant merits in improving the predictive accuracy in comparison with control methods. 展开更多
关键词 GM(1 1)model Minimum norm quadratic unbiased estimation(MINQUE) Total least-squares(TLS) Unequal-precision measurement variance component estimation(VCE)
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A Mean-variance Problem in the Constant Elasticity of Variance(CEV) Model
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作者 Hou Ying-li Liu Guo-xin Jiang Chun-lan 《Communications in Mathematical Research》 CSCD 2015年第3期242-252,共11页
In this paper, we focus on a constant elasticity of variance (CEV) modeland want to find its optimal strategies for a mean-variance problem under two constrainedcontrols: reinsurance/new business and investment (n... In this paper, we focus on a constant elasticity of variance (CEV) modeland want to find its optimal strategies for a mean-variance problem under two constrainedcontrols: reinsurance/new business and investment (no-shorting). First, aLagrange multiplier is introduced to simplify the mean-variance problem and thecorresponding Hamilton-Jacobi-Bellman (HJB) equation is established. Via a powertransformation technique and variable change method, the optimal strategies withthe Lagrange multiplier are obtained. Final, based on the Lagrange duality theorem,the optimal strategies and optimal value for the original problem (i.e., the efficientstrategies and efficient frontier) are derived explicitly. 展开更多
关键词 constant elasticity of variance model MEAN-variance optimal strategy
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COMPLETE CONVERGENCE OF ERROR VARIANCE ESITIMATES UNDER Ф-MIXING ERROR IN LINEAR MODELS
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作者 薛留根 《Acta Mathematica Scientia》 SCIE CSCD 1994年第4期417-425,共9页
In this paper,we consider the estimates d of error variance d2=Var(ei) in the linear models Yi=x' iβ+ei(i= 1, 2, ... ). We study the complete convergence of dm2-o2 when the error {ei }is a sequence of identically... In this paper,we consider the estimates d of error variance d2=Var(ei) in the linear models Yi=x' iβ+ei(i= 1, 2, ... ). We study the complete convergence of dm2-o2 when the error {ei }is a sequence of identically distributed p-mixing variables. And we also obtain the better convergence rates when {ei} is not identically distribution 展开更多
关键词 ERROR LINEAR COMPLETE ESITIMATES CONVERGENCE MIXING modelS OF UNDER variance
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Heteroscedasticity check in nonlinear semiparametric models based on nonparametric variance function
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作者 QU Xiao-yi LIN Jin-guan 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期401-409,共9页
The assumption of homoscedasticity has received much attention in classical analysis of regression. Heteroscedasticity tests have been well studied in parametric and nonparametric regressions. The aim of this paper is... The assumption of homoscedasticity has received much attention in classical analysis of regression. Heteroscedasticity tests have been well studied in parametric and nonparametric regressions. The aim of this paper is to present a test of heteroscedasticity for nonlinear semiparametric regression models with nonparametric variance function. The validity of the proposed test is illustrated by two simulated examples and a real data example. 展开更多
关键词 heteroscedasticity check nonlinear semiparametric regression model asymptotic normality nonparametric variance function
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Variance Estimation for High-Dimensional Varying Index Coefficient Models
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作者 Miao Wang Hao Lv Yicun Wang 《Open Journal of Statistics》 2019年第5期555-570,共16页
This paper studies the re-adjusted cross-validation method and a semiparametric regression model called the varying index coefficient model. We use the profile spline modal estimator method to estimate the coefficient... This paper studies the re-adjusted cross-validation method and a semiparametric regression model called the varying index coefficient model. We use the profile spline modal estimator method to estimate the coefficients of the parameter part of the Varying Index Coefficient Model (VICM), while the unknown function part uses the B-spline to expand. Moreover, we combine the above two estimation methods under the assumption of high-dimensional data. The results of data simulation and empirical analysis show that for the varying index coefficient model, the re-adjusted cross-validation method is better in terms of accuracy and stability than traditional methods based on ordinary least squares. 展开更多
关键词 HIGH-DIMENSIONAL Data Refitted Cross-Validation VARYING INDEX COEFFICIENT modelS variance ESTIMATION
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Portfolio Choice under the Mean-Variance Model with Parameter Uncertainty 被引量:1
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作者 何朝林 许倩 《Journal of Donghua University(English Edition)》 EI CAS 2015年第3期498-503,共6页
Assuming the investor is uncertainty-aversion,the multiprior approach is applied to studying the problem of portfolio choice under the uncertainty about the expected return of risky asset based on the mean-variance mo... Assuming the investor is uncertainty-aversion,the multiprior approach is applied to studying the problem of portfolio choice under the uncertainty about the expected return of risky asset based on the mean-variance model. By introducing a set of constraint constants to measure uncertainty degree of the estimated expected return,it built the max-min model of multi-prior portfolio,and utilized the Lagrange method to obtain the closed-form solution of the model,which was compared with the mean-variance model and the minimum-variance model; then,an empirical study was done based on the monthly returns over the period June 2011 to May 2014 of eight kinds of stocks in Shanghai Exchange 50 Index. Results showed,the weight of multi-prior portfolio was a weighted average of the weight of mean-variance portfolio and that of minimumvariance portfolio; the steady of multi-prior portfolio was strengthened compared with the mean-variance portfolio; the performance of multi-prior portfolio was greater than that of minimum-variance portfolio. The study demonstrates that the investor can improve the steady of multi-prior portfolio as well as its performance for some appropriate constraint constants. 展开更多
关键词 portfolio choice mean-variance model parameter uncertainty multi-prior approach constraint constant
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Correction of Left Ventricular Doppler Echocardiographic Measurements for Physiological Variances Using a Novel Optimized Multivariable Allometric Model in Healthy Chinese Han Adults
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作者 Guihua Yao Xiangyun Chen +12 位作者 Wenjing Yang Qing Zhang Jing Liu Huan Liang Hui Sun Yao Xu Li Wang Jinfeng Xu Cheng Zhang Fengrong Sun Mei Zhang Xueying Zeng Yun Zhang 《Engineering》 SCIE EI CAS 2022年第9期115-122,共8页
Most left ventricular(LV)Doppler measurements vary significantly with age and gender,making it necessary to correct them for physiological variances.We aimed to verify the hypothesis that different Doppler measurement... Most left ventricular(LV)Doppler measurements vary significantly with age and gender,making it necessary to correct them for physiological variances.We aimed to verify the hypothesis that different Doppler measurements correlate nonlinearly with different biometric variables raised to different scaling factors and exponents.In this work,a total of 23 LV Doppler parameters were measured in 1224 healthy Chinese adults.An optimized multivariable allometric model(OMAM)and scaling equations were developed in 70%of the subjects(group A),and the reliability of the model and equations was verified using the remaining 30%of the subjects(group B)as well as 183 overweight subjects(group C).The single-variable isometric model(SVIM)with body surface area(BSA)as a scaling variable was used for comparison.Before correction,all 23 LV Doppler parameters correlated significantly with one or more of the biometric variables.In group B,gender differences were found in 47.8%(11/23)of the parameters and were eliminated in 81.8%(9/11)of the parameters after correction with OMAM.The successful correction rate with OMAM was 100%(23/23)in group B and 82.6%(19/23)in group C.New reference values for corrected Doppler measurements independent of biometric variables were established.The SVIM with BSA successfully corrected none of the 23 parameters.In conclusion,different LV Doppler parameters allometrically correlated with one or more of the biometric variables.The novel OMAM developed in this study successfully corrected the effects of the physiological variances of most biometric variables on Doppler measurements in healthy and overweight subjects,and was found to be far superior to the SVIM.However,whether the OMAM equations can be applied to other ethnicities,obese subjects,and pathological conditions requires further investigation. 展开更多
关键词 Doppler echocardiography Physiological variance Allometric model Normal reference values
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Asymptotic Normality of Pseudo-LS Estimator of Error Variance in Partly Linear Autoregressive Models
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作者 WU Xin-qian TIAN Zheng JU Yan-wei 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第4期617-622,共6页
Consider the model Yt = βYt-1+g(Yt-2)+εt for 3 〈 t 〈 T. Hereg is anunknown function, β is an unknown parameter, εt are i.i.d, random errors with mean 0 andvariance σ2 and the fourth moment α4, and α4 are ... Consider the model Yt = βYt-1+g(Yt-2)+εt for 3 〈 t 〈 T. Hereg is anunknown function, β is an unknown parameter, εt are i.i.d, random errors with mean 0 andvariance σ2 and the fourth moment α4, and α4 are independent of Y8 for all t ≥ 3 and s = 1, 2.Pseudo-LS estimators σ, σ2T α4τ and D2T of σ^2,α4 and Var(ε2↑3) are respectively constructedbased on piecewise polynomial approximator of g. The weak consistency of α4T and D2T are proved. The asymptotic normality of σ2T is given, i.e., √T(σ2T -σ^2)/DT converges indistribution to N(0, 1). The result can be used to establish large sample interval estimatesof σ^2 or to make large sample tests for σ^2. 展开更多
关键词 partly linear autoregressive model error variance piecewise polynomial pseudo-LS estimation weak consistency asymptotic normality
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Investigating seasonality,policy intervention and forecasting in the Indian gold futures market:a comparison based on modeling non‑constant variance using two different methods
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作者 Rupel Nargunam William W.S.Wei N.Anuradha 《Financial Innovation》 2021年第1期1390-1404,共15页
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
关键词 Gold futures prices ARIMA models Non-constant variance ARCH and GARCH models Box-Cox power transformation Forecast errors
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Convertible Bond Pricing Based on Exponential Variance Gamma Model
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作者 Min Tan 《经济管理学刊(中英文版)》 2018年第2期155-162,共8页
Due to the‘spike and tail’ phenomenon of asset returns,the applicability of the Black-Scholes model for pricing convertible bonds has been questioned,and the variance gamma model can cope well with this phenomenon a... Due to the‘spike and tail’ phenomenon of asset returns,the applicability of the Black-Scholes model for pricing convertible bonds has been questioned,and the variance gamma model can cope well with this phenomenon and solve the ‘volatility smile dilemma’.This paper combines the variance gamma model with the least squares Monte Carlo simulation method to empirically analyze the Everbright convertible bond based on its high activity in the Chinese market.In this paper,the predicted price and the actual price are compared,and the applicability of the variance gamma model in the Chinese convertible bond market is analyzed.Empirical results show that the fitting price predicted by the variance gamma model is consistent with the actual price trend,indicating that the method is applicable to the Chinese convertible bond market. 展开更多
关键词 CONVERTIBLE BOND variance GAMMA model MONTE Carlo Simulation
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Performance of CMIP6 models in simulating the dynamic sea level:Mean and interannual variance
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作者 Hongying Chen Zhuoqi He +1 位作者 Qiang Xie Wei Zhuang 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第1期34-40,共7页
本研究采用卫星测高数据与第六次国际耦合模式比较计划(CMIP6)海平面动力进行对比,重点针对40S-40N地区的动力海平面(DSL),评估了模式对其平均态与年际变率的综合模拟能力,结果表明,对于DSL平均态的模拟,模式与观测结果非常吻合,模式之... 本研究采用卫星测高数据与第六次国际耦合模式比较计划(CMIP6)海平面动力进行对比,重点针对40S-40N地区的动力海平面(DSL),评估了模式对其平均态与年际变率的综合模拟能力,结果表明,对于DSL平均态的模拟,模式与观测结果非常吻合,模式之间的差异较小.其中,副热带北大西洋是模拟偏差和模式间差异较为显著的区域,对于DSL年际变率的模拟,模式之间保持较高的一致性,但是,模式与观测结果存在明显差异,模式普遍低估了DSL的年际方差;其中,误差大值区域出现在副热带西边界流附近,模式分辨率会影响CMIP6对中小尺度海洋过程的重现能力,这可能是导致CMIP6历史模拟出现误差的原因之一. 展开更多
关键词 动力海平面 CMIP6 平均态 年际变率 模式分辨率
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Research on Mean-Variance Portfolio Model with singular Covariance Matrix
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作者 Xinmeng Wang Haiyue Jin +1 位作者 Junjie Bai Yicheng Hong 《经济管理学刊(中英文版)》 2017年第2期60-66,共7页
关键词 协变性 矩阵解 模型 发现方法 模拟试验 非退化
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Identification Method for RLG Random Errors Based on Allan Variance and Equivalent Theorem 被引量:3
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作者 唐江河 付振宪 邓正隆 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2009年第3期273-278,共6页
An identification method using Allan variance and equivalent theorem is proposed to identify non-stationary sensor errors mixed out of different simple noises. This method firstly derives the discrete Allan variances ... An identification method using Allan variance and equivalent theorem is proposed to identify non-stationary sensor errors mixed out of different simple noises. This method firstly derives the discrete Allan variances of all component noises inherent in noise sources in terms of their different equations; then the variances are used to estimate the parameters of all component noise models; finally, the original errors are represented by the sum of the non-stationary component noise model and the equivalent m... 展开更多
关键词 Allan variance equivalent theorem NON-STATIONARY auto-regressive and moving average model ring laser gyro
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基于mean-variance的服务集群负载均衡方法 被引量:7
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作者 包晓安 魏雪 +2 位作者 陈磊 胡国亨 张娜 《电信科学》 北大核心 2017年第1期1-8,共8页
大量并发请求任务进行分配时,负载调度机制是通过最小化响应时间及最大化节点利用率实现网络中节点的负载均衡,在基于遗传算法的负载均衡算法中,适应度函数设计对服务集群负载均衡效率产生重要的影响。对此提出了一种基于mean-variance... 大量并发请求任务进行分配时,负载调度机制是通过最小化响应时间及最大化节点利用率实现网络中节点的负载均衡,在基于遗传算法的负载均衡算法中,适应度函数设计对服务集群负载均衡效率产生重要的影响。对此提出了一种基于mean-variance的服务集群负载均衡方法对适应度函数进行优化,采用投资组合选择模型mean-variance进行最小化响应时间,以得到每个服务器资源利用率的权重,从而获得最优的分配组合,进而提高适应度函数的准确性和有效性。在不同服务环境下与其他模型进行比较,仿真结果表明,本文的负载均衡算法在节点利用率和响应时间方面使服务集群得到了更好的均衡。 展开更多
关键词 负载均衡 mean-variance模型 遗传算法 负载调度
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Variance Gamma过程与股票期权定价中的波动率偏度的纠正 被引量:6
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作者 奚炜 《系统工程》 CSCD 北大核心 2003年第1期29-32,共4页
针对 Black- Scholes期权定价模型在股票期权定价中的波动率偏度的定价偏差 ,介绍一种新的改进模型来纠正波动率偏度 ,这种改进模型是通过将 Black- Scholes期权定价模型中的布朗运动过程替换为 variance gamma过程来实现的。在给出相... 针对 Black- Scholes期权定价模型在股票期权定价中的波动率偏度的定价偏差 ,介绍一种新的改进模型来纠正波动率偏度 ,这种改进模型是通过将 Black- Scholes期权定价模型中的布朗运动过程替换为 variance gamma过程来实现的。在给出相应欧式看涨期权价格的解析解的基础上 ,对改进模型的定价性能进行实证检验。 展开更多
关键词 varianceGamma过程 股票期权定价 波动率偏度 期权定价模型 恒生指数期权 股票价格
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摩擦市场条件下的Mean-Variance-Skewness模型
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作者 周洪涛 王宗军 曾宇容 《华中科技大学学报(自然科学版)》 EI CAS CSCD 北大核心 2006年第6期122-124,共3页
在投资组合选择模型中考虑了资产收益率分布中正的偏度水平,并通过引入一些市场摩擦因素建立了摩擦市场条件下的Mean-Variance-Skewness模型.提出了一个新的遗传算法加速其搜索收敛过程,解决了该模型的计算复杂性问题.在该模型框架内对... 在投资组合选择模型中考虑了资产收益率分布中正的偏度水平,并通过引入一些市场摩擦因素建立了摩擦市场条件下的Mean-Variance-Skewness模型.提出了一个新的遗传算法加速其搜索收敛过程,解决了该模型的计算复杂性问题.在该模型框架内对交易费用和税收等市场摩擦因素进行了敏感性分析.研究证明资产收益率分布的偏度水平是与投资者的决策相关的,市场摩擦因素对投资者的决策行为也有直接的影响.因此,考虑摩擦市场条件下基于正偏度水平偏好的最优投资组合模型对投资者有很强的实践指导价值. 展开更多
关键词 资本市场 Mean-variance-Skewness模型 摩擦市场 遗传算法
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