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221.
Representation theorem and local asymptotic minimax theorem are derived for nonparametric estimators of the distribution function on the basis of randomly truncated data. The convolution-type representation theorem asserts that the limiting process of any regular estimator of the distribution function is at least as dispersed as the limiting process of the product-limit estimator. The theorems are similar to those results for the complete data case due to Beran (1977, Ann. Statist., 5, 400–404) and for the censored data case due to Wellner (1982, Ann. Statist., 10, 595–602). Both likelihood and functional approaches are considered and the proofs rely on the method of Begun et al. (1983, Ann. Statist., 11, 432–452) with slight modifications.Division of Biostatistics, School of Public Health, Columbia Univ. 相似文献
222.
一类Schrodinger方程的周期解和谱方法 总被引:1,自引:0,他引:1
本文利用半群理论讨论了一类非线性非自共轭Schrodinger方程周期初边值解的存在唯一性,以及它的Fourier谱方法的可解性,稳定性和收敛性 相似文献
223.
224.
In this paper, we introduce a map between the q-deformed gauge fields defined on the GLq(N) -covariant quantum hyperplane and the ordinary gauge fields. Perturbative analysis of the q-deformed QED at the classical level is presented and gauge fixing à la BRST is discussed. Another star product defined on the hybrid (q,h) -plane is explicitly constructed. 相似文献
225.
We prove the following.THEOREM. Let be the fundamental group of a finite graph of groups with finitely generated vertex groups
G
v
having asdim G
v
n
for all vertices v. Then asdim n+1.This gives the best possible estimate for the asymptotic dimension of an HNN extension and the amalgamated product. 相似文献
226.
Anatolij Dvurečenskij 《International Journal of Theoretical Physics》2004,43(11):2169-2185
Pseudo-effect algebras are partial algebras (E;+,0,1) with a partially defined addition + which is not necessarily commutative and therefore with two complements, left and right. If they satisfy a special kind of the Riesz decomposition property, they are intervals in unital po-groups. The general comparability property in unital po-groups with strong unit (G,u), allows to compare elements of G in some intervals with Boolean ends. Such a po-group is always an -group admitting a state. We prove that every such (G,u) is a subdirect product of linearly ordered unital po-groups. 相似文献
227.
Emmanuel Chetcuti Anatolij Dvurečenskij 《International Journal of Theoretical Physics》2004,43(2):369-384
Let S be an inner product space and let E(S) (resp. F(S)) be the orthocomplemented poset of all splitting (resp. orthogonally closed) subspaces of S. In this article we study the possible states/charges that E(S) can admit. We first prove that when S is an incomplete inner product space such that dim S/S < , then E(S) admits at least one state with a finite range. This is very much in contrast to states on F(S). We then go on showing that two-valued states can exist on E(S) not only in the case when E(S) consists of the complete/cocomplete subspaces of S. Finally we show that the well known result which states that every regular state on L(H) is necessarily -additive cannot be directly generalized for charges and we conclude by giving a sufficient condition for a regular charge on L(H) to be -additive. 相似文献
228.
229.
Communiols A-D (1-4), new tetrahydrofuran and bis-tetrahydrofuran derivatives, have been isolated from cultures of the coprophilous fungus Podospora communis, and identified by spectroscopic methods. 相似文献
230.
A concise synthesis of the isolaurepinnacin skeleton 6 was achieved via the intermolecular allylation of the α-acetoxy ether 3 followed by ring-closing metathesis. This methodology was successfully applied to the convergent synthesis of the oxocene 15, an advanced synthetic intermediate for the total synthesis of laurencin. 相似文献