Abstract

This paper shows how notions of vagueness in preferences and judgments of personal probabilities can be accommodated within an axiomatization of subjective expected utility by the use of extraneous scaling probabilities and gambles on consequences. The representational form obtained says that the subjective expected utility of one act exceeds the subjective expected utility of a second act whenever the first is preferred to the second. The paper also explores the possibility of obtaining this representational form under Savage's formulation, which does not use extraneous probabilities, and discusses difficulties encountered in this approach.