In this paper, a general formulation for a model of market-based agent-resource systems is proposed, building on the computational ecosystem model of Huberman and Hogg [in The Ecology of Computation, edited by B. A. Huberman (North-Holland, Amsterdam, 1988)]. Our approach, based on one-step Markov processes and Van Kampen’s large-system-size expansion, allows the effects of fluctuations to be explored, particularly in finite systems where stochastic processes assume increasing importance.

• Received 24 May 1993

DOI:https://doi.org/10.1103/PhysRevE.49.3833