Fuzzy coalitional structures (alternatives)

The uncertainty of expectations and vagueness of the interests belong to
natural components of cooperative situations, in general. Therefore, some
kind of formalization of uncertainty and vagueness should be included in
realistic models of cooperative behaviour. This paper attempts to contribute
to the endeavour of designing a universal model of vagueness in cooperative
situations. Namely, some initial auxiliary steps toward the development of
such a model are described. We use the concept of fuzzy coalitions suggested
in [1], discuss the concepts of superadditivity and convexity, and introduce a
concept of the coalitional structure of fuzzy coalitions.
The first version of this paper [10] was presented at the Czech-Japan
Seminar in Valtice 2003. It was obvious that the roots of some open questions
can be found in the concept of superadditivity (with consequences on some
other related concepts), which deserve more attention. This version of the
paper extends the previous one by discussion of alternative approaches to
this topic.