The problem of the theory of aggregate (market) demand, which is,
according to Walras, the sum of demands of individuals maximizing their
«utilities» (preferences functions), consists in absence at such a demand of
analytical properties of individual demand («impossibility theorems» of Gorman
and of Sonnenschein-Mantel-Debreu). The problem’s resolving on the basis of
notion «the statistical ensemble of consumers» as initial object is suggested.
A corresponding modification of the Cassel-Wald model of economic equilibrium
with representation of collective preferences via vector field is presented. It
is shown that the Arrow-Debreu model with unified commodities (goods and
factors) is not consistent with the theory of market demand.
Keywords: Statistical ensemble of
consumers, market demand, field of preferences, economic equilibrium,
Cassel-Wald model, Arrow-Debreu model.