The theoretical modeling in complex physical systems may be aimed at an imp
roved precision of empirical description or a deeper physical understanding
of the phenomena. The Preisach-type empirical product model of hysteresis
as well as a zero temperature Monte Carlo simulation of the magnetization p
rocess of an Ising-like dipolar system are discussed as an illustration of
modeling examples. (C) 2000 Elsevier Science B.V. All rights reserved.