A Theory of Subjective Expected Utility with Vague Preferences.

This report 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 scaling probabilities and lotteries on consequences. The representation 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 report also explores the possibility of obtaining this representation without using scaling probabilities.