English

Concentration of measures via size biased couplings

Probability 2011-06-20 v2

Abstract

Let YY be a nonnegative random variable with mean μ\mu and finite positive variance σ2\sigma^2, and let YsY^s, defined on the same space as YY, have the YY size biased distribution, that is, the distribution characterized by E[Yf(Y)]=\mu E f(Y^s) for all functions ff for which these expectations exist. Under a variety of conditions on the coupling of Y and YsY^s, including combinations of boundedness and monotonicity, concentration of measure inequalities hold. Examples include the number of relatively ordered subsequences of a random permutation, sliding window statistics including the number of m-runs in a sequence of coin tosses, the number of local maximum of a random function on a lattice, the number of urns containing exactly one ball in an urn allocation model, the volume covered by the union of nn balls placed uniformly over a volume n subset of d dimensional Euclidean space, the number of bulbs switched on at the terminal time in the so called lightbulb process, and the infinitely divisible and compound Poisson distributions that satisfy a bounded moment generating function condition.

Keywords

Cite

@article{arxiv.0906.3886,
  title  = {Concentration of measures via size biased couplings},
  author = {Subhankar Ghosh and Larry Goldstein},
  journal= {arXiv preprint arXiv:0906.3886},
  year   = {2011}
}

Comments

Concentration results for the number of isolated vertices have been removed from this version, and with corrections, posted jointly with Martin Raic in http://arxiv.org/abs/1106.0048