Chamberlinian Spatial Computable General Equilibrium Modelling: A Theoretical Framework

In this paper, a multi-regional multi-sectoral computable general equilibrium model is developed by bringing together different strands of theoretical reasoning. These are as follows: input–output analysis, gravity modelling, the theory of intra-industry trade and the theory of general equilibrium under conditions of monopolistic competition. The innovation in this approach is the assumption that, within each sector, a large number of different brands of output are produced. Households like diversity of consumption and diversity of inputs is a productive factor for firms. The number of brands produced in each sector and region is endogenous. A certain amount of fixed costs per brand imposes an upper bound on the number of available brands. Factor markets are perfectly competitive, while monopolistic competition prevails on goods markets. The equilibrium solution of the model closely resembles models which have been applied on an ad hoc basis in regional science before, but it is well founded in modern economic theory now. In particular, trade flows obey a gravity law in equilibrium.