Aggregation of decomposable measures with application to utility theory

This paper investigates the eventwise aggregations of decomposable measures preserving the same decomposable property. These operations are obtained by solving a functional equation closely related to the bisymmetry property. Known results for probability as well as possibility measures can be derived as particular cases of our approach. In addition, the unicity of weighted consensus functions is proved in the Archimedean case. An extension of Von Neumann-Morgenstern utility theory is outlined, where probabilities are changed into decomposable measures.