We consider voting games induced by anonymous and top-unanimous social choice functions. The class of such social choice functions is quite broad, including every “t-refinement” of the Plurality Rule, Plurality with a Runoff, the Majoritarian Compromise and the Single Transferable Vote,...

We propose an aggregation model which explains stereotype formation under the attribution hypothesis. We show, under very mild axioms, that an observer can be thought of perceiving a group in terms of her subjective opinion about the representativeness of subgroups, as well as a possible...

A social choice hyperfunction picks a non-empty set of alternatives at each admissible preference profile over sets of alternatives. We analyze the manipulability of social choice hyperfunctions. We identify a domain D[lambda] of lexicographic orderings which exhibits an impossibility of the...

We characterize sets of alternatives which are Condorcet winners according to preferences over sets of alternatives, in terms of properties defined on preferences over alternatives. We state our results under certain preference extension axioms which, at any preference profile over alternatives,...

We show that the Copeland solution is equivalent to the minisum principle which requires to choose the candidate(s) who beat all remaining contenders in the smallest total number of steps.