This is the first of two guest pieces by Paul Ormerod, the author of “Positive Linking” (Amazon USA; Amazon UK) and several other important books on non-equilibrium economics.
Paul and I have been research colleagues and friends for over a decade now, and I regard him as the foremost exponent of multi-agent and network economics today. As regular readers will know, I prefer a “tops down” approach to economics over the multi-agent approach, mainly because the phenomenon of emergence is a significant conceptual barrier between the “macro” systems we wish to describe and the “micro” behaviour of the individual entities that comprise the system. Paul has a flair for being able to develop models that penetrate that barrier successfully. I particularly like the model in this paper on competition and market structure, and I use it in my own lectures as an example of how competition should be modelled by economists, in contrast to the Neoclassical myths of perfect & imperfect competition and oligopoly.