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arXiv · 1002.1544

Generalized Dirichlet distributions on the ball and moments

Franck Barthe·Fabrice Gamboa·Li-Vang Lozada-Chang·Alain Rouault
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Abstract

The geometry of unit $N$-dimensional $\ell_{p}$ balls has been intensively investigated in the past decades. A particular topic of interest has been the study of the asymptotics of their projections. Apart from their intrinsic interest, such questions have applications in several probabilistic and geometric contexts (Barthe et al. 2005). In this paper, our aim is to revisit some known results of this flavour with a new point of view. Roughly speaking, we will endow the ball with some kind of Dirichlet distribution that generalizes the uniform one and will follow the method developed in Skibinsky (1967), Chang et al. (1993) in the context of the randomized moment space. The main idea is to build a suitable coordinate change involving independent random variables. Moreover, we will shed light on a nice connection between the randomized balls and the randomized moment space.

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Franck Barthe, Fabrice Gamboa, Li-Vang Lozada-Chang, Alain Rouault. 2010-10-21. Generalized Dirichlet distributions on the ball and moments. https://arxiv.org/abs/1002.1544

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