BLO CLASS UNDER THE CHANGE OF MEASURE

The purpose of the paper is to study the behavior of the classes of functions of bounded lower oscillation under the change of measure given by the weight w More specifically, we provide sharp upper and lower bounds for the norm of the inclusion BLO -> BLO (w) in terms of A(infinity) constant of the weight. The results hold in the general context of probability spaces equipped with a treelike structure.