Arrow’s theorem [1963] states that a social welfare function (SWF) that simultaneously satis.es completeness, transitivity, independence of irrelevant alternatives (IIA) and Pareto principle is necessarily dictatorial in the sense that the social decision on any pair of candidates coincides...

We characterize binary decision rules which are independent and strongly paretian,or independent and almost strongly paretian when the individual preferences and the collective preference are weak orders.

This paper considers voting situations in which the vote takes place iteratively. If a coalition replaces the status quo a with a contestant b, then b becomes the new status quo, and the vote goes on until a candidate is reached that no winning coalition is willing to replace. It is well known...