ABSTRACT
From the perspective of descriptive theory, the term solution set commonly refers to a set of alternatives that includes all possible outcomes of a voting process, given certain behavioral assumptions. A ‘best’ alternative might be defined as an alternative that is most preferred by all members of a coalition of some requisite size. A majority winner beats every other alternative through the same majority coalition; a Condorcet winner beats every other alternative but beats different alternatives through different majority coalitions. Thus, a majority winner is necessarily a Condorcet winner but the reverse is not true. If majority preference is weak, the notion of a Condorcet winner generalizes to the set of unbeaten alternatives. This chapter introduces a related definition: a Condorcet loser in X is an alternative that is beaten by every other alternative in X.
