Source: Ann. Probab. Volume 32, Number 3B
(2004), 2526-2544.
Let qn be a continuous density function in n-dimensional Euclidean space. We think of qn as the density function of some random sequence Xn with values in
. For I⊂[1,n], let XI denote the collection of coordinates Xi, i∈I, and let
denote the collection of coordinates Xi, i∉I. We denote by
the joint conditional density function of XI, given
. We prove measure concentration for qn in the case when, for an appropriate class of sets I, (i) the conditional densities
, as functions of xI, uniformly satisfy a logarithmic Sobolev inequality and (ii) these conditional densities also satisfy a contractivity condition related to Dobrushin and Shlosman’s strong mixing condition.
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