q-Functions and extreme topological measures

Functions provide a method for constructing topological measures. We give necessary and sufficient conditions for a composition of a q-function and a topological measure to be a topological measure. Regular and extreme step q-functions are characterized by certain regions in Rn. Then extreme q-functions are used to study extreme topological measures. For example, we prove (under some assumptions on the underlying set) that given n, there are different types of extreme topological measures with values 0, 1/n, . . . , 1. In contrast, in the case of measures the only extreme points are {0, 1}-valued, i.e., point masses.  2005 Elsevier Inc. All rights reserved.