A Model of Monopolistic Competition with Personal Income Dispersion

We introduce non-homothetic preferences in the Dixit-Stiglitz model of monopolistic competition, and enquire about the effects of a change in income dispersion on the firms' optimal decisions and market equilibrium. Income dispersion, modeled as a mean preserving spread, is shown to affect only the degree of product differentiation under the standard negligibility hypothesis on the firms' decision making process, while it generates a positive co-movement of demand and demand elasticity, when this assumption is removed and the price index effect is taken into account