Most often this is when two or more politically similar candidates divide the vote for the more popular end of the political spectrum. While Perata was on top after all the first-place votes were counted, Quan edged him out 51 to 49 percent after second- and third-choice votes were added.
Ranked choice voting RCV -- sometimes called "instant runoff" -- was approved by city voters in Research concludes that IRV is one of the less-manipulable voting methods, with theorist Nicolaus Tideman noting that, "alternative vote is quite resistant to strategy"  and Australian political analyst Antony Green dismissing suggestions of tactical voting.
Tactical voting in IRV seeks to alter the order of eliminations in early rounds, to ensure that the original winner is challenged by a stronger opponent in the final round. IRV is more likely to elect the Condorcet winner than plurality voting and traditional runoff elections.
This implies that IRV is susceptible to tactical voting in some circumstances. It is incompatible with the later-no-harm criterion, so IRV does not meet this criterion. Yet because the Republican led in first choices and only narrowly lost the final instant runoff, his backers would have been highly unlikely to pursue such a strategy.
After that disaster, the city modified the voting machine software used to allocate and count second- and third-place votes. For offices decided by RCV, voters rank their first, second and third choices. The first time it was used in a San Francisco election was Spoiler effect The spoiler effect is when a difference is made to the anticipated outcome of an election due to the presence on the ballot paper of a candidate who predictably will lose.
For example, in a three-party election where voters for both the left and right prefer the centrist candidate to stop the "enemy" candidate winning, those voters who care more about defeating the "enemy" than electing their own candidate may cast a tactical first preference vote for the centrist candidate.
Mutual majority criterion The mutual majority criterion states that "if an absolute majority of voters prefer every member of a group of candidates to every candidate not in that group, then one of the preferred group must win".
A chart in the article on the Schulze method compares various ranked ballot methods. In that election, most supporters of the candidate who came in second a Republican who led in first choices preferred the Condorcet winner, a Democrat, to the IRV winner, the Progressive Party nominee.
IRV, like all preferential voting methods which are not positionaldoes not meet this criterion. That is, each receives fewer votes than a single opponent on the unpopular end of the spectrum who is disliked by the majority of voters but who wins from the advantage that, on that unpopular side, he or she is unopposed.
Independence of clones criterion The independence of clones criterion states that "the election outcome remains the same even if an identical candidate who is equally preferred decides to run. In that sense, the Republican candidate was a spoiler even though leading in first choice support.
He called ranked-choice voting "an injustice. IRV does not meet this criterion: If voters vote according to the same ordinal preferences in both rounds, criteria can be applied to two-round systems of runoffs, and in that case, each of the criteria failed by IRV is also failed by the two-round system as they relate to automatic elimination of trailing candidates.
Every seat was won with a majority of the vote, including several where results would have been different under plurality voting. An IRV method reduces this problem, since the voter can rank the marginal candidate first and the mainstream candidate second; in the likely event that the fringe candidate is eliminated, the vote is not wasted but is transferred to the second preference.San Francisco is one of a handful of major American cities that use ranked-choice voting to elect a mayor.
The San Francisco system works like this: When voters cast their ballot, they get to rank. Ranked Choice Voting / Instant Runoff; Ranked Choice Voting / Instant Runoff. Ranked choice voting (RCV) makes democracy more fair and functional.
It works in a variety of contexts. It is a simple change that can have a big impact. San Francisco, California. San Francisco uses a ranked-choice voting system that allows voters to select their top-three favorites. The candidates with the least votes are eliminated in rounds until there's a winner; the.
Jun 09, · It may sound complicated, but it works smoothly in countries from Australia to Ireland to New Zealand.
More than a dozen American cities have. San Francisco's new mayor will be chosen in June by a system few voters can fully explain, much less understand. It's a process even the guy who runs the city's elections struggles to describe. Ranked choice voting (RCV) -- sometimes called "instant runoff" -- was approved by city voters in American organizations that promote IRV (such as FairVote) identified IRV as "instant-runoff voting" as recently asbut shifted to referring to IRV as "ranked-choice voting" as jurisdictions using it such as San Francisco, California; Maine; and Minneapolis, Minnesota codified the term in their laws.Download