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991.
We establish local asymptotic normality of thinned empirical point processes, based on n i.i.d. random elements, if the probability
of thinning satisfies
. It turns out that the central sequence is determined by the limit of the coefficient of variation of the tangent function. The central sequence depends only on the total number
of nonthinned observations if and only if this limit is 1 or –1. In this case under suitable regularity conditions, an asymptotically efficient estimator of the underlying parameter can be based on
only. An application to density estimation leads to a fuzzy set density estimator, which is efficient in a parametric model. In a nonparametric setup, it can also outperform the usual kernel density estimator, depending on the values of the density and its second derivative. 相似文献
992.
Vincent Borrelli Fabiano Brito Olga Gil-Medrano 《Annals of Global Analysis and Geometry》2003,23(2):129-140
We construct a one-parameter family of unit smooth vector fieldsglobally defined on the sphere
2k+1 for k 2, with energyconverging to the energy of the unit radial vector field, which isdefined on the complementary of two antipodal points. So we prove thatthe infimum of the energy of globally defined unit smooth vector fieldsis
相似文献
993.
Suthep?SuantaiEmail author Chanan?Sudsukh 《Southeast Asian Bulletin of Mathematics》2003,26(2):337-350
In this paper, we give the matrix characterizations from any normal vector-valued FK-space containing ø(X) into scalar-valued sequence space c(q) and by applying this result, we also obtain necessary and sufficient conditions for infinite matrices mapping the sequence spaces
, and Fr(X, p) into the space c(q), where p = (Pk) and q = (qk) are bounded sequences of positive real numbers and r 0.AMS Subject Classification (2000): 46A45. 相似文献
994.
For a sequence of integrable random variables, we introduce a new set of conditions called Cesàro -Integrability and Strong Cesàro -Integrability and show that, for <1/2, these conditions that are strictly weaker than Cesàro Uniform Integrability and Strong Cesàro Uniform Integrability respectively, are sufficient for WLLN and SLLN to hold for a sequence of pairwise independent random variables. For some special kinds of dependent sequences of random variables also, Cesàro -integrability for appropriate is shown to be sufficient for WLLN to hold. 相似文献
995.
A global compactness result for singular elliptic problems involving critical Sobolev exponent 总被引:11,自引:0,他引:11
Let be a bounded domain such that . Let be a (P.S.) sequence of the functional . We study the limit behaviour of and obtain a global compactness result.
996.
Michael Eisermann 《Transactions of the American Mathematical Society》2003,355(12):4825-4846
It is a well-known paradigm to consider Vassiliev invariants as polynomials on the set of knots. We prove the following characterization: a rational knot invariant is a Vassiliev invariant of degree if and only if it is a polynomial of degree on every geometric sequence of knots. Here a sequence with is called geometric if the knots coincide outside a ball , inside of which they satisfy for all and some pure braid . As an application we show that the torsion in the braid group over the sphere induces torsion at the level of Vassiliev invariants: there exist knots in that can be distinguished by -invariants of finite type but not by rational invariants of finite type. In order to obtain such torsion invariants we construct over a universal Vassiliev invariant of degree for knots in .
997.
A Variation of an Extremal Theorem Due to Woodall 总被引:1,自引:0,他引:1
We consider a variation of an extremal theorem due to Woodall [12, or 1, Chapter 3] as follows: Determine the smallest even integer (3C1,n), such that every n-term graphic sequence = (d1, d2,..., dn) with term sum () = d1 + d2 + ... + dn (3C1,n) has a realization G containing a cycle of length r for each r = 3,4,...,l. In this paper, the values of (3Cl,n) are determined for l = 2m – 1,n 3m – 4 and for l = 2m,n 5m – 7, where m 4.AMS Mathematics subject classification (1991) 05C35Project supported by the National Natural Science Foundation of China (Grant No. 19971086) and the Doctoral Program Foundation of National Education Department of China 相似文献
998.
Raffaele Vitolo 《Acta Appl Math》2002,72(1-2):133-154
The C-spectral sequence was introduced by A. M. Vinogradov in the late Seventies as a fundamental tool for the study of the algebro-geometric properties of jet spaces and differential equations. A spectral sequence arises from the contact filtration of the modules of forms on jet spaces of a fibring (or on a differential equation). In order to avoid serious technical difficulties, the order of the jet space is not fixed, i.e., computations are performed on spaces containing forms on jet spaces of any order. In this paper we show that there exists a formulation of Vinogradov's C-spectral sequence in the case of finite-order jet spaces of a fibred manifold. We compute all cohomology groups of the finite-order C-spectral sequence. We obtain a finite-order variational sequence which is shown to be naturally isomorphic with Krupka's finite-order variational sequence. 相似文献
999.
We show that real k-structures coincide for k=1,2 on all formal groups for which multiplication by 2 is an epimorphism. This enables us to give explicit polynomial generators for the Morava K(n)-homology of BSpin and BSO for n=1,2. 相似文献
1000.
Jacchieri SG 《Molecular diversity》1998,4(3):199-207
Six computer-based combinatorial libraries,including tetrapeptide sequences (generated with fiveamino acids) and conformations (generated with fivemain chain and three side chain rotamers), wereobtained and sequence-conformation probabilities werecalculated with a molecular and statistical mechanicsprocedure. The structural motifs -helix,-sheet, 310-helix, reverse turn I and-turn were focused in these calculations. Itis shown that sequence-conformation-probabilitysurfaces provide a broad view of structural changesaccompanying changes in sequence. Numerical indicesare defined to enable comparisons between frequenciesof occurrence of these structural motifs in peptidelibraries and in a database of low sequence identityprotein structures. Fine details ofsequence-conformation-probability surfaces show theeffect of point mutations. Broad comparisons betweendifferent regions of these surfaces indicate how toselect the occurrence of structural motifs in thecombinatorial synthesis of peptide chains. 相似文献