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141.
Let Um be an m×m Haar unitary matrix and U[m,n] be its n×n truncation. In this paper the large deviation is proven for the empirical eigenvalue density of U[m,n] as m/n→λ and n→∞. The rate function and the limit distribution are given explicitly. U[m,n] is the random matrix model of quq, where u is a Haar unitary in a finite von Neumann algebra, q is a certain projection and they are free. The limit distribution coincides with the Brown measure of the operator quq. 相似文献
142.
143.
In a recent paper, Willmot (2015) derived an expression for the joint distribution function of the time of ruin and the deficit at ruin in the classical risk model. We show how his approach can be applied to obtain a simpler expression, and by interpreting this expression by probabilistic reasoning we obtain solutions for more general risk models. We also discuss how some of Willmot’s results relate to existing literature on the probability and severity of ruin. 相似文献
144.
Werner Kunz 《Computational Statistics》2007,22(4):521-531
This paper presents a method for visualizing competitive market structures based on scanner panel data where asymmetries are
taken into account. For this, I combined consumer choice models based on mixed logit models with three-mode principal component
analysis. This approach can be used to unfold a competitive market structure map. The methodology presented is able to quantify
the clout and receptivity of various brands. The results can then be visualized over time. Using this approach, guidelines
for promotional activities of new brands can be provided, and possible threats from the competition detected. 相似文献
145.
Takashi Nakamura 《Journal of Number Theory》2007,123(1):1-9
In this paper, we define λ-joint, a′-joint, (λ,λ)-joint, (λ,a′)-joint and (a′,a′)-joint t-universality of Lerch zeta functions and consider the relations among those. Next we show the existence of (λ,λ)-joint t-universality. Finally, we also show the existence of λ-joint, a′-joint, (λ,a′)-joint and (a′,a′)-joint t-universality by using inversion formulas. 相似文献
146.
Let (F,G) be a pair of matrices defined over an arbitrary field, Fn × n, Gn × m. Consider the natural action of GLn x GLm on this pair given by (F,G) ? (gFg-1,gGh-1), where (g,h) ∈ GLn × GLm. This action is of interest in system theory as well as the representation theory of quivers. In this paper we study the stabilizer subgroup of this action stab(F,G), i.e. . 相似文献
147.
148.
We consider a family of random locations, called intrinsic location functionals, of periodic stationary processes. This family includes but is not limited to the location of the path supremum and first/last hitting times. We first show that the set of all possible distributions of intrinsic location functionals for periodic stationary processes is the convex hull generated by a specific group of distributions. We then focus on two special subclasses of these random locations. For the first subclass, the density has a uniform lower bound; for the second subclass, the possible distributions are closely related to the concept of joint mixability. 相似文献
149.
The radius of spatial analyticity for solutions of the KdV equation is studied. It is shown that the analyticity radius does not decay faster than as time t goes to infinity. This improves the works of Selberg and da Silva (2017) [30] and Tesfahun (2017) [34]. Our strategy mainly relies on a higher order almost conservation law in Gevrey spaces, which is inspired by the I-method. 相似文献
150.
Let be a finite field and a positive integer. In this paper, we find a new combinatorial method to determine weight enumerators of reducible cyclic codes and their dual codes of length over , which just generalize results of Zhu et al. (2015); especially, we also give the weight enumerator of a cyclic code, which is viewed as a partial Melas code. Furthermore, weight enumerators obtained in this paper are all in the form of power of a polynomial. 相似文献