  We investigate Yang-Lee zeros of grand partition functions as truncated
fugacity polynomials of which coefficients are given by the canonical partition
functions $Z(T,V,N)$ up to $N \leq N_{\text{max}}$. Such a partition function
can be inevitably obtained from the net-baryon number multiplicity distribution
in relativistic heavy ion collisions, where the number of the event beyond
$N_{\text{max}}$ has insufficient statistics, as well as canonical approaches
in lattice QCD. We use a chiral random matrix model as a solvable model for
chiral phase transition in QCD and show that the closest edge of the
distribution to real chemical potential axis is stable against cutting the tail
of the multiplicity distribution. The similar behavior is also found in lattice
QCD at finite temperature for Roberge-Weiss transition. In contrast, such a
stability is found to be absent in the Skellam distribution which does not have
phase transition. We compare the number of $N_{\text{max}}$ to obtain the
stable Yang-Lee zeros with those of critical higher order cumulants.
