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931.
Gé rard Letac Dhafer Malouche Stefan Maurer 《Proceedings of the American Mathematical Society》2002,130(7):2107-2114
For 0,$"> this note computes essentially the set of in such that the entire series in defined by has all its coefficients non-negative. If and are independent random variables which have respectively Bernoulli and negative binomial distributions, denote by the distribution of . The above problem is equivalent to finding the set of 0$"> such that exists; this set is a finite union of intervals and may be the first example of this type in the literature. This gives the final touch to the classification of the natural exponential families with variance functions of Babel type, i.e. of the form , where is a polynomial with degree
932.
933.
It is already known that the uniformly minimum variance unbiased (UMVU) estimator of the generalized variance always exists for any natural exponential family. However, in practice, this estimator is often difficult to obtain. This paper provides explicit forms of the UMVU estimators for the bivariate and symmetric multivariate gamma models, which are diagonal quadratic exponential families. For the non-independent multivariate gamma models, it is shown that the UMVU and the maximum likelihood estimators are not proportional. 相似文献
934.
王元恒 《应用泛函分析学报》2008,10(3):219-227
推广了Banach空间中广义拟变分包含的概念,研究了无限族广义集值拟变分包含的解的存在性及其迭代逼近问题.所得结果改进和推广了一些最新的成果. 相似文献
935.
Reconstructability analysis is viewed as a process of investigating the possibilities of reconstructing desirable properties of overall systems from the knowledge of the corresponding properties of their various subsystems. The reconstructability analysis consists of procedures for generating meaningful reconstruction hypotheses, procedures for the evaluation of the reconstruction hypotheses, and procedures for making various decisions regarding the acceptance of evaluated reconstruction hypotheses, generation of additional reconstruction hypotheses, termination of the analysis and the like.The paper discusses the evaluation of reconstruction hypotheses when the systems under consideration are possibilistic behavior systems. It is shown that a principle of maximum ambiguity, similar to the principle of maximum entropy for probabilistic systems, can be used for possibilistic systems. It is also shown that the unbiased (maximum ambiguity) reconstruction can be determined by a simple join procedure, in a similar fashion as for probabilistic systems. The join procedure for possibilistic systems turns out to be computationally simpler than the one for probabilistic systems. The paper also describes a general procedure for determining the reconstruction family. 相似文献
936.
Jan van Mill 《Topology and its Applications》1982,13(1):43-57
In this paper we describe sixteen topological types in βω?ω. Among others, we show that there is a weak P-point x ∈ βω?ω which is a limit point of some ccc subset of βω?ω?{x} and that there is a point y ∈ βω?ω which is a limit point of some countable subset of βω?ω?{y} but not of any countable discrete subset of βω?ω?{y}. 相似文献
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940.
J. A. Tussupov 《Siberian Mathematical Journal》2007,48(6):1106-1114
We construct an autostable 2 nilpotent group with no Scott family of finitary formulas but having a unique constructivization up to autoequivalence. 相似文献