English

Projections of probability distributions: A measure-theoretic Dvoretzky theorem

Probability 2011-04-22 v3

Abstract

Many authors have studied the phenomenon of typically Gaussian marginals of high-dimensional random vectors; e.g., for a probability measure on Rd\R^d, under mild conditions, most one-dimensional marginals are approximately Gaussian if dd is large. In earlier work, the author used entropy techniques and Stein's method to show that this phenomenon persists in the bounded-Lipschitz distance for kk-dimensional marginals of dd-dimensional distributions, if k=o(log(d))k=o(\sqrt{\log(d)}). In this paper, a somewhat different approach is used to show that the phenomenon persists if k<2log(d)log(log(d))k<\frac{2\log(d)}{\log(\log(d))}, and that this estimate is best possible.

Keywords

Cite

@article{arxiv.1102.3438,
  title  = {Projections of probability distributions: A measure-theoretic Dvoretzky theorem},
  author = {Elizabeth Meckes},
  journal= {arXiv preprint arXiv:1102.3438},
  year   = {2011}
}

Comments

Minor errors corrected resulting in cosmetic changes to statements of some theorems. Assumptions on the underlying distribution have been clarified; a small amount of additional discussion added