No abstract

A veto theory is constructed for a finite committee and a measure space of alternatives.Strategical and descriptive concepts of veto and effectivity functions are extended to the model. We show that under some natural assumptions a neutral veto correspondence can be represented by a real veto power function. As in the discrete case we prove that a stable VC is well-behaved from above and from below, that a convex VC is stable, and that a maximal VC is stable if and only if it is superadditive and subadditive.

No abstract

We study the structure of unstable power mechanisms. A power mechanism is modeled by an interaction form, the solution of which is called a settlement. By stability, we mean the existence of some settlement for any preference profile. Configurations that produce instability are called cycles. We introduce a stability index that measures the difficulty of emergence of cycles. Structural properties such as exactness, superadditivity, subadditivity and maximality provide indications about the type of instability that may affect the mechanism. We apply our analysis to strategic game forms in the context of Nash-like solutions or core-like solutions. In particular, we establish an upper bound on the stability index of maximal interaction forms.