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41.
Chen Zhou 《Extremes》2008,11(3):281-302
In this paper, we build a two-step estimator , which satisfies , where is the well-known maximum likelihood estimator of the extreme value index. Since the two-step estimator can be calculated easily as a function of the observations, it is much simpler to use in practice. By properly choosing the
first step estimator, such as the Pickands estimator, we can even get a shift and scale invariant estimator with the above property.
The author thanks Laurens de Haan for motivating this work and giving helpful comments. The author also thanks two anonymous
referees for their useful comments. 相似文献
42.
Norm Inequalities for Commutators of Self-adjoint Operators 总被引:3,自引:0,他引:3
Fuad Kittaneh 《Integral Equations and Operator Theory》2008,62(1):129-135
Let A, B, and X be bounded linear operators on a complex separable Hilbert space. It is shown that if A and B are self-adjoint with and for some real numbers a
1, a
2, b
1, and b
2, then for every unitarily invariant norm|||·|||,
. If, in addition, X is positive, then
. These norm inequalities generalize recent related inequalities due to Kittaneh, Bhatia-Kittaneh, and Wang-Du.
相似文献
43.
44.
S. Ya. Grinshpon 《代数通讯》2013,41(11):4273-4282
We study primary groups containing proper fully invariant subgroups isomorphie to the group. The admissable sequence of Ulm–Kaplansky invariants for primary groups is introduced. Using these sequences, If-groups are described in the classes of seperable and periodically complete groups. 相似文献
45.
46.
L. P. Vlasov 《Mathematical Notes》1997,61(1):38-47
Functionals (vector measures) defined on the spaceC(Q, X) of continuous abstract functions (whereQ is a compact Hausdorff space andX is a Banach space) and attaining their norm on the unit sphere are considered. A characterization of such functionals is
given in terms of the Radon-Nikodym derivative of the vector measure with respect to the variation of the measure and in terms
of analogs of the derivative. Applications to the characterization of finite-codimensional subspaces with the best approximation
property are given. Similar results are obtained for the spaceB(Q, Σ, X) of uniform limits of simple functions.
Translated fromMatematicheskie Zametki, Vol. 61, No. 1, pp. 45–56, January, 1997.
Translated by V. E. Nazaikinskii 相似文献
47.
Andrzej Kornacki 《Applications of Mathematics》1997,42(1):71-77
Necessary and sufficient conditions are derived for the inclusions
and
to be fulfilled where
are some classes of invariant linearly sufficient statistics (Oktaba, Kornacki, Wawrzosek (1988)) corresponding to the Gauss-Markov models
, respectively. 相似文献
48.
Alvise Sommariva 《Numerical Functional Analysis & Optimization》2013,34(9):1198-1223
In this article, we discuss two methods for the compression of multivariate discrete measures, with applications to node reduction in numerical cubature and least-squares approximation. The methods are implemented in the Matlab computing environment, in dimension two. 相似文献
49.
50.
Summary In [8] we found a class of overlapping asymmetric self-similar measures on the real line, which are generically absolutely
continuous with respect to the Lebesgue measure. Here we construct exceptional measures in this class being singular. 相似文献