  The analysis of the statistical and dynamical fluctuations in nucleus-nucleus
collisions on an event-by-event basis strongly relies on a comparison with
specially constructed artificial events where statistical fluctuations and
kinematical correlations are under control. In this paper, we present a novel,
analytical method of constructing reference events based on independent
emission, modified by the energy/momentum constraint, which can lead to a
better understanding of the nature of the observed final-state fluctuations.
This approach can be easily used in the analysis of other topics in the heavy
ion field (e.g. flow, HBT etc.) allowing more precise measurements.
