  This work is motivated by the relaxation data for materials which exhibit a
change of the relationship between the fractional power-law exponents when
different relaxation peaks in their dielectric susceptibility are observed.
Within the proposed framework we derive a frequency-domain relaxation function
fitting the whole range of the two-power-law dielectric spectroscopy data with
independent low- and high-frequency fractional exponents \gamma\ and -\alpha,
respectively. We show that this effect results from a contribution of different
processes. For high frequencies it is determined by random stops and movement
of relaxing components, and the low-frequency slope is caused by clustering in
their temporal changes.
