EXAMPLE 6 Sequential Pairwise Voting

Assume we have four candidates and that the agenda is , , , . Consider the following sequence of three preference list ballots:

Rank Number of Voters (3)
First
Second
Third
Fourth

419

The first one-on-one pits against , and wins by a score of 2 to 1 (meaning that two of the voters—the two not in the middle—prefer to , and one of the voters prefers to ). Thus, is eliminated and A moves on to confront . Because wins this one on one (by a score of 3 to 0), A is eliminated. Finally, takes on , and wins by a score of 2 to 1. Thus, is the winner.