Proceedings of the Ninth International Symposium on Imprecise Probability: Theories and Applications (ISIPTA 2015), pp. 305 – 314, July 2015.
Poster prize: 4th place.We investigate how to model indifference with choice functions. We take the coherence axioms for choice functions proposed by Seidenfeld, Schervisch and Kadane as a source of inspiration, but modify them to strengthen the connection with desirability. We discuss the properties of choice functions that are coherent under our modified set of axioms and the connection with desirability. Once this is in place, we present an axiomatisation of indifference in terms of desirability. On this we build our characterisation of indifference in terms of choice functions.