Elementary non-Archimedean utility theory

Abstract

A non-Archimedean utility representation theorem for independent and transitive preference orderings that are partially continuous on some convex subset and satisfy an axiom of incommensurable preference for elements outside that subset is proven. For complete preference orderings, the theorem is deduced directly from the classical von Neumann-Morgenstern theorem; in the absence of completeness, Aumann's [Aumann, R.J., 1962. Utility theory without the completeness axiom. Econometrica 30 (3), 445-462] generalization is utilized.von Neumann-Morgenstern utility Discontinuous preferences Ordered vector space Hyperreals Non-Archimedean field