Instant Runoff Voting in San Francisco
San Francisco’s first Instant Runoff Voting (IRV) election occurred in November 2004. Prior to that, San Francisco used Top-Two Runoff (TTR), a system in which a Plurality Voting election is held, and if no candidate receives a majority of the votes, a later “runoff” is held between the two top vote getters. Here we attempt to summarize the effect IRV has had in SF.
- Save money, by eliminating the expense of holding a second (runoff) election
- Increase voter turnout, by eliminating supposedly low-turnout runoff elections
- From this page on IRV costs, election integrity activist Joyce McCloy explains:
Maybe IRV saves money, but there isn’t a solid cost savings analysis using San Francisco’s actual election department’s net annual expenditures. From San Francisco’s Budget Reports:
2000-2001 Actual 9,024,000
2001-2002 Actual 13,872,000 includes the cost of $1,322,849 for a runoff election & $150,000 due to litigation costs
2002-2003 Actual 8,610,553
2003-2004 Actual 15,204,781
2004-2005 Actual 10,400,868
2005-2006 Actual 11,930,228
2006-2007 Actual 10,062,052 (budget) 9,126,318
2007-2008 Actual 14,839,686 (budget) 19,809,917
- Warren D. Smith, a Princeton math Ph.D. who has researched election issues for over a decade, created this analysis of San Francisco’sofficial election turnout data. It shows that, overall, election turnout has actually decreased, albeit by a statistically insignificant amount.
Voting Method Regret (50-50) Regret (100% honest) #Agreements with (true-utility-based)
Condorcet Winner (when CW exists)
SociallyBest 0 0 12653 Range 0.16329 0.04802 11796 Approval 0.215 0.18983 10997 Borda 0.28234 0.093768 10821 CondorcetLR 0.35602 0.13781 10342 Top2Runoff 0.49909 0.23604 8823 IRV 0.50115 0.21684 8387 Top3IRV 0.53124 0.23683 7842 Plurality 0.64371 0.33137 6357 RandomBallot 0.72014 0.72305 5185 RandomWinner 1 1 2930 SociallyWorst 2.0024 2.0098 6
What we can see here is that, from a pure democratic-ness standpoint, IRV is a little better than Plurality Voting. And TTR is approximately equal in quality to IRV. However, IRV has a number of concerning side effects whose practical importance must be also taken into account.
IRV cannot be counted in precincts, because it is not “additive”. This is explained by a Princeton math Ph.D. here. A more layman-friendly description of the implication of this fact comes from the San Francisco city elections page:
“Due to the requirement that all ballots must be centrally tallied in City Hall and not at the polling places, the Department of Elections has not set a date for releasing any preliminary results using the ranked-choice voting method.”
This appeared on their website for several weeks after their 2008 RCV elections. The need to transport votes to a central location for tabulation is of great concern to election integrity activists. It means greater susceptibility to fraud.
IRV increases the probability of tie/near-tie scenarios (i.e. election disputes and recounts are more probable).
mehey man.can you do me a favor?coworkersurewhat’s upmeokay, i need to use you as a guinea pig for a voting op-ed i’m writing.it will just take a minute.coworkerkmedon’t look up anything.i want to see how much a typical sf voter knows about our voting system.so you know how we rank our choices on the ballot?so like, X>Y>Z means the voter likes X first, then Y, then Z.make sense?coworkeryesmeokay, so look at this list and tell me who wins.% of voters – their ranking35% W > Y > Z > X17% X > Y > Z > W32% Y > Z > X > W16% Z > X > Y > Wcoworkerwell… i could do math here right?do you want me to or not?meyes.tell me who wins.without looking anything up.coworkerlooks like Ymewhy do you think it’s Y?how did you arrive at that answer?coworkerbecause in the first row it’s next to the winning W, and in between row#2, and #3, it’s pretty high upbasically according to weighted average it’d roughly be a leadermenope.the winner is X.