Necessary and sufficient conditions for the addivity of ordinal utility functions are well known. In this paper a necessary and sufficient condition for the addivity of von Neumann-Morgenstern utility ...

Moreover, some non-trivial constrained additive utility functions are presented. We also open a problem concerning the existence of a minimal relation characterizing a considered constrained ...

Certain plausible independence properties lead to a quasi-additive utility function for life years and health status. Particular attention is given to utility functions for life years exhibiting ...