Progress in the bond graph representations of economics and population dynamics

Abstract The dynamics of the marketplace are amenable to a bond graph description. Franksen pointed out that the economic laws of Walras are the equivalents of the Kirchhoff laws and that this implied a network or structural aspect of the marketplace. We begin with this observation and fully develop the sign and signal-flow conventions. More importantly, we conduct a survey of the economics and related literatures in order to recast the conventional theory into the form of constitutive relations. That work is summarized and extended in this paper. Other new contributions described are associated with economic populations. (An instance of such a population is a group of machines, each of which undergoes a life cycle and then is replaced, refueled or maintained.) The discussion is illustrated with examples. One example is a simple market whose dynamics are characterized by a chaotic attractor, another example is a bond graph of the recycling of a commodity.