  Fourth-order cumulants of physical quantities have been used to characterize
the nature of a phase transition. In this paper we report some Monte Carlo
simulations to illustrate the behavior of fourth-order cumulants of
magnetization and energy across second and first-order transitions in the phase
diagram of a well known spin-1 Ising model. Simple ideas from the theory of
thermodynamic fluctuations are used to account for the behavior of these
cumulants.
