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971.
972.
Summary A data set on types of congenital heart malformations for sibling pairs of Fraser and Hunter (1975) is analyzed exactly for
quasi-independence with Monte Carlo methods. Exactp-values are computed for a test of parameter significance and a test of goodness-of-fit which contradict the model of quasiindependence
and confirm an earlier analysis of MacGibbon (1983). 相似文献
973.
974.
张建斌 《新疆大学学报(理工版)》2004,21(3):329-331
通过通讯软件将微机与BAS100A测试仪连接在一起,在菜单的提示下进行分析样品的测试、绘图、数据的处理、数据存盘等,整个过程轻松、自如、方便、快捷,软件的设计达到了预期的目的。 相似文献
975.
Let G be a finitely generated torsion-free group, which is a metabelian product of Abelian groups. We establish a criterion for endomorphisms satisfying some extra restriction to be invertible in G. Test sets for IA-endomorphisms of G are described and its test rank computed. 相似文献
976.
Douglas G Bonett 《Statistics & probability letters》1985,3(3):127-129
A linear model is defined for logarithmic and linear functions of negative multinomial frequency counts. A closed-form estimator of the model parameters, estimator covariance matrix, and general Wald test are derived under the assumption of negative multinomial sampling. 相似文献
977.
讨论从加卸载循环的应力-应变表征曲线提取得到的各材料力学性能,尤其是关于屈服和塑性变形的特征参数。包括加卸载弹性模量E_L~T,E_u~T;屈服点的表征参数:屈服应力σ_s~T,屈服应变ε_s~N,屈服应变能U_s;热激活塑性变形的表征参数:活化体积V_τ和活化能ΔH。讨论这些参数对温度和应变率的依赖关系,寻求由这些特征参数作表述,或是存在于这些参数之间的经验关系或规律。 相似文献
978.
For a restricted class of problems a mathematical model of microscopic degradation processes, statistical kinetics, is developed and linked throughacceleration transforms to the information which can be obtained from a system in which the only observable sign of degradation is sudden and catastrophic failure. The acceleration transforms were developed in accelerated life testing applications as a tool for extrapolating from the observable results of an accelerated life test to the dynamics of the underlying degradation processes. A particular concern of a physicist attempting to interpreted the results of an analysis based on acceleration transforms is determining the physical species involved in the degradation process. These species may be (a) relatively abundant or (b) relatively rare. The main results of this paper are a theorem showing that for an important subclass of statistical kinetic models, acceleration transforms cannot be used to distinguish between cases a and b, and an example showing that in some cases falling outside the restrictions of the theorem, cases a and b can be distinguished by their acceleration transforms. 相似文献
979.
Summary The problem is to estimate the mean of the normal distribution under the situation where there is vague information that the
mean might be equal to zero. A minimax property of the preliminary test estimator obtained by the use of AIC (Akaike information
Criterion) procedure is proved under a loss function based on the Kullback-Leibler information measure. 相似文献
980.
Christine M. Waternaux 《Journal of multivariate analysis》1984,14(3):323-335
The limiting distribution of the likelihood ratio statistic Wq for testing the hypothesis of equality of q characteristic roots of a covariance matrix is studied in the case of nonnormal populations. It is shown, both theoretically and empirically, that the limiting distribution of Wq is not robust to departures from normality and that Wq cannot be used for nonnormal populations with long tails. For the class of elliptical populations the limiting distribution of Wq can be expressed in close form. A corrected test statistic, Wq*, is proposed that can be used in principal component analysis when sampling from elliptical populations. 相似文献