  It is demonstrated that in low multiplicity sample, the increase of the
fluctuation of event-factorial-moments with the diminishing of phase space
scale, called ``erraticity'', are dominated by the statistical fluctuations.
The erraticity behavior observed at NA27 experiment can be readily reproduced
by pure statistical fluctuations. Applying erraticity analysis to a high
multiplicity sample is recommended and the method is improved at very high
multiplicity case as well.
