This article obtains demand functions for risky assets without making a priori assumptions about the form of the utility function. In a simple portfolio model, the envelope theorem is applied to the ...

Fractional demand systems are utility derived demands having quantities or budget shares proportional to ag + bf, where g and f are functions of income and a and b vary across goods and are functions ...

The assumptions of completeness, two-term consistency, transitivity and continuity are necessary for constructing a utility function over a set of preferences. 4.