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991.
Raymond F. Gittings 《Topology and its Applications》1980,11(2):149-159
In this paper we obtain characterizations of metrizable spaces, paracompact M-spaces, Moore spaces and semimetrizable spaces in terms of the way those spaces are embedded in their Stone-?ech compactification. In addition, we give an internal characterization of paracompact M-spaces which we use in the proof of the embedding characterization. 相似文献
992.
993.
The strong consistency of least squares estimates in multiple regression models is established under minimal assumptions on the design and weak dependence and moment restrictions on the errors. 相似文献
994.
Summary Exact robustness studies against non-normality have been carried out for test of independence based on the four multivariate
criteria: Hotelling's trace,U
(p)
, Pillai's trace,V
(p)
, Wilks' criterion,W
(p)
, and Roy's largest root,L
(p)
. The density functions ofU
(p)
,W
(p)
andL
(p)
have been obtained in the canonical correlation case and further the moments ofU
(p)
and m.g.f. ofV
(p)
have been derived. All of the study is based on Pillai's distribution of the characteristic roots under violations. Numerical
results for the power function have been tabulated for the two-roots case. Slight non-normality does not affect the independence
test seriously.V
(2) is found to be most robust against nonnormality.
Yu-Sheng Hsu is now with Georgia State University, Atlanta. 相似文献
995.
The criterion robustness of the standard likelihood ratio test (LRT) under the multivariate normal regression model and also the inference robustness of the same test under the univariate set up are established for certain nonnormal distributions of errors. Restricting attention to the normal distribution of errors in the context of univariate regression models, conditions on the design matrix are established under which the usual LRT of a linear hypothesis (under homoscedasticity of errors) remains valid if the errors have an intraclass covariance structure. The conditions hold in the case of some standard designs. The relevance of C. R. Rao's (1967 In Proceedings Fifth Berkeley Symposium on Math. Stat. and Prob., Vol. 1, pp. 355–372) and G. Zyskind's (1967, Ann. Math. Statist.38 1092–1110) conditions in this context is discussed. 相似文献
996.
997.
998.
999.
1000.
M. Van De Vel 《Topology and its Applications》1983,16(2):181-206
It is shown that two-dimensional convex structures with certain natural properties are join-hull commutative. The main intermediate step is the computation of the so-called exchange number. We also give two examples of three-dimensional convexities which are not join-hull commutative. The second one has certain additional properties showing that the main theorem is sharp in many other respects. These properties are obtained from a study of convex hyperspaces. 相似文献