Here we present a more formal approach to the ideas underlying modeling—a model of modeling. Our discussion relies on the mental modeling ideas developed by Holland et al. (1986) for creating artificial learning systems. We focus on trying to model a world that varies over discrete time steps (though one could obviously apply these ideas to other types of systems). The basic outline of the underlying ideas are presented in figure 3.2. In the top half of the figure, we represent the real world that we are interested in modeling; in the lower half, we depict our model.
