User:BetterVotingAdvocacy/Negative vote-counting approach for pairwise counting: Difference between revisions

The negative counting approach is an alternative method of doing [[pairwise counting]]. It is faster, depending on implementation, when voters don't rank all of the candidates (or when they rank multiple candidates last), because it takes advantage of the fact that in most ranked voting elections, voters are assumed to prefer every candidate they ranked over every candidate they left unranked.

This advice is less relevant when write-ins are allowed, however, because even if a voter ranks a candidate last among the candidates named on their ballot, they are still implicitly ranking that candidate above all of the write-in candidates they didn't rank on their ballot. So if last-ranked candidates aren't counted, then it may be necessary to modify how the calculation is done to avoid giving the impression that the vote totals are accurate for the matchups involving write-in candidates.

It is perhaps possible to make a special marking for a last-choice candidate that indicates they are not preferred over any of the on-ballot (regular) candidates, but that they are preferred over all write-in candidates. It would then only be necessary to record negative votes for matchups involving write-in candidates who are ranked above the last-choice candidate on some ballots. This would mean making at most two additional marks for every last-ranked candidate on a ballot, because in practice voters are only allowed to write in one candidate. This can be compared to the regular approach to dealing with write-ins at [[Pairwise counting#Dealing with write-in candidates]].