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971.
Suppose that {z(t)} is a non-Gaussian vector stationary process with spectral density matrixf(λ). In this paper we consider the testing problemH: ∫π−π K{f(λ)} dλ=cagainstA: ∫π−π K{f(λ)} dλ≠c, whereK{·} is an appropriate function andcis a given constant. For this problem we propose a testTnbased on ∫π−π K{f(λ)} dλ=c, wheref(λ) is a nonparametric spectral estimator off(λ), and we define an efficacy ofTnunder a sequence of nonparametric contiguous alternatives. The efficacy usually depnds on the fourth-order cumulant spectraf4Zofz(t). If it does not depend onf4Z, we say thatTnis non-Gaussian robust. We will give sufficient conditions forTnto be non-Gaussian robust. Since our test setting is very wide we can apply the result to many problems in time series. We discuss interrelation analysis of the components of {z(t)} and eigenvalue analysis off(λ). The essential point of our approach is that we do not assume the parametric form off(λ). Also some numerical studies are given and they confirm the theoretical results. 相似文献
972.
John Kornak Mark E. Irwin Noel Cressie 《Statistical Inference for Stochastic Processes》2006,9(1):31-46
The study of stochastic processes can take many forms. Theoretical properties are important to ensure consistent model definition.
Statistical inference on unknown parameters is equally important but can be difficult. This is principally because many of
the standard assumptions for proving consistency and asymptotic normality of estimators involve independence and homogeneity.
In the case where inference is concerned with detecting change in a spatial process from one time point to another, a statistical-computing
approach can be rewarding. Regardless of the complexity of the stochastic process, if simulating from it is relatively easy,
then detecting change is possible using a Monte Carlo approach. The methodology is applied in a military scenario, where a
country’s defensive posture changes as a function of its perceived threat. For tactical-decision purposes, it is extremely
important to know whether the country’s perceived threat level has changed. 相似文献
973.
《Journal of computational science》2014,5(3):408-414
The significant increase in the complexity and autonomy of the hardware systems renders the verification of the functional safety of each individual component as well as of the entire system a complex task and underlines the need for integrated, model based tools that would assist this process. In this paper the authors present such a tool, coupled with an approach to functional safety analysis, based on the integration of functional tests into the model itself. The analysis of the resulting model is done through a stochastic Bayesian model. This approach strives to both bypass the necessity for costly hardware testing and integrate the functional safety analysis into an intuitive component development process. 相似文献
974.
假设检验的相对稳定性 总被引:2,自引:0,他引:2
郑祖康^[1]提出了数理统计学中一个有意义的新问题-假设检验的稳定性。但是,由于稳定性定义的条件太强,从而通常检验统计量的稳定性并不好。本文根据假设检验的实际意义,定义了假设检验的相对稳定性,讨论了一类常用检验统计量的相对稳定性的一些性质,作为特例,得到似然比检验的相对稳定性的性质。 相似文献
975.
Sadanori Konishi C. G. Khatri 《Annals of the Institute of Statistical Mathematics》1990,42(3):561-580
Inference procedures for interelass and intraclass correlations are given in the multivariate context of familial data for which measurements are taken on more than one characteristic. Unified estimators are proposed based on a certain class of unbiased estimators of covariance matrices. Asymptotic distributions of the proposed estimators are derived under the assumption of multivariate normality. The results can be used to construct approximate confidence intervals and test procedures.Research supported by the Department of Statistics, the Pennsylvania State University and the Air Force Office of Scientific Research under Grant AFSO-88-0030.Institute of Statistical Mathematics 相似文献
976.
我国教育投资与经济增长的协整分析与误差修正模型 总被引:4,自引:0,他引:4
翁莉娟 《数学的实践与认识》2008,38(10)
近年来"教育产业化"已成为一个热门话题,教育界、经济学家、政府官员等社会各界人士仁者见仁、智者见智,有学者提出用教育促进消费、拉动内需、推动经济发展的观点.然而,教育投资与经济增长的关系究竟如何呢?以国家统计局发布的1952~2006年度的统计数据为基础,对我国教育投资与经济增长的内在依存关系进行实证分析,结果表明短期内扩大教育投资对经济增长不产生作用,但长期来看教育投资对经济增长具有显著的拉动作用. 相似文献
977.
对寿命分布为威布尔分布,加速方程为逆幂律的情况,由简单步进应力加速寿命试验所获得的数据,给出了有关参数和加速系数的点和区间估计,并论证了这种估计的存在和唯一性. 相似文献
978.
979.
A. W. Bowman M. C. Jones I. Gijbels 《Journal of computational and graphical statistics》2013,22(4):489-500
Abstract This article provides a test of monotonicity of a regression function. The test is based on the size of a “critical” bandwidth, the amount of smoothing necessary to force a nonparametric regression estimate to be monotone. It is analogous to Silverman's test of multimodality in density estimation. Bootstrapping is used to provide a null distribution for the test statistic. The methodology is particularly simple in regression models in which the variance is a specified function of the mean, but we also discuss in detail the homoscedastic case with unknown variance. Simulation evidence indicates the usefulness of the method. Two examples are given. 相似文献
980.