%0 Journal Article %T Nested identification of subjective probabilities %A Jacques H. Dreze %J SERIEs %@ 1869-4195 %D 2012 %I %R 10.1007/s13209-011-0049-4 %X The theory of games against nature relies on complete preferences among all conceivable acts (case 1). Aumann and Dr¨¨ze (Am Econ J Microecon 1(1):1¨C16, 2009) consider situations where preferences are defined only for a given set of acts (case 2). We extend these results to situations where (i) only the set of optimal elements from a given set of acts is known (case 3); (ii) only a single optimal act is known (case 4). To these four cases correspond four nested sets of admissible subjective probabilities. Cases 3 and 4 define the extent to which probabilities must be specified to solve a decision problem. %K Games %K Decisions %K Probability %K Elicitation %K D81 %K C72 %U http://link.springer.com/article/10.1007/s13209-011-0049-4