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Initiative 318 (IRV) & Election Methods

Initiative 318 (IRV) & Election Methods. A presentation of issues addressed by Washington State Initiative 318 and a discussion of possible alternatives. Abstract. Two big changes 318 introduces: Changing plurality voting to IRV voting. Abolishing the primary election.

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Initiative 318 (IRV) & Election Methods

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  1. Initiative 318 (IRV)& Election Methods A presentation of issues addressed by Washington State Initiative 318 and a discussion of possible alternatives.

  2. Abstract • Two big changes 318 introduces: • Changing plurality voting to IRV voting. • Abolishing the primary election. • What this presentation will discuss: • What is IRV? • What are alternative methods? • and how do you judge them? • What are the implications of rolling the primary election into the general election? Nathan Herring

  3. Glossary Strategic Voting -- When you vote contrary to your preferences in order to get a better outcome. It is generally preferable to have systems that minimize the utility of such voting. Also called Tactical Voting. Viable Candidates -- Candidates with a real shot at winning the election; strategy can often change depending on the number of viable candidates. Exhausted Ballots -- In ranking systems, ballots where every candidate has been eliminated. Nathan Herring

  4. Glossary, continued Clones -- Candidates that voters rank the same relative to the rest of the candidates. Sincere Voting -- Opposite of strategic voting; voting (all of) your true preferences. Truncated Preferences -- Not ranking or rating every candidate. Spoiling -- Voting for third parties & independents splits votes off of a viable (secondarily-preferred) candidate, causing them to lose. Nathan Herring

  5. Election Methods

  6. What is IRV? IRV is Instant Run-off Voting. • Instead of voting for one candidate, you rank all the candidates. • If no candidate wins the majority, there is a virtual run-off. • The candidate with the least first-choice votes is stricken from the rankings on the ballots. • Some ballots may end up having a new first-choice. • Check again for a winner, and if not keep striking candidates until there is a winner. Nathan Herring

  7. Demonstration http://www.chrisgates.net/irv/ Nathan Herring

  8. Where is IRV in use? • In Australia, it’s called Alternative Vote and is used to elect their Representatives and members of some lower Parliaments. • In California, it’s called Ranked Choice Voting (RCV), and first used this fall. Nathan Herring

  9. Alternative Methods & Types Type 1: “Regular” ballot methods • Plurality, the status quo • Approval Type 2: Ordinal (Ranked) ballot methods • Instant Runoff Voting (IRV) • Borda • Condorcet, or Instant Round-Robin Voting Type 3: Cardinal (Rated) ballots Nathan Herring

  10. Type 1: “Regular” ballot methods • These methods employ the ballot we use today, where there are ovals next to candidate names. • Validation and calculation, however, may change. Nathan Herring

  11. Plurality The candidate with the most votes wins. • Voting for non-viable (e.g., third party) candidates, can be “spoiling”. • “Lesser of two evils” • It is, however, simple. • Easy to vote -- Choose one. • Easy to strategize -- Pick your favorite viable candidate. Nathan Herring

  12. Approval Also, the candidate with the most votes wins. • You can vote for (or “approve”) as many candidates as you want. • No spoiling -- You can vote for third parties. • If your favorite candidate is non-viable, you still have to approve of your favorite of the viable candidates. • Ballots remain simple, but there’s less validation a ballot reader can do. Nathan Herring

  13. Type 2: Ranked ballot methods • Requires a change to the ballot to allow voter to be able to rank candidates (1-2-3). • Requires changes to voting machines and tabulation processes. • Provide mechanisms to not have to have run-offs or staged elections (e.g., primary and general). • Increases complexity of (re)counting process. Nathan Herring

  14. Instant Run-off Voting • Voter can register their third-party preference without “spoiling”. • Strategy for elections with more than two viable candidates is not obvious. • Only one choice, the topmost, is ever considered during a run-off round. • The top choice(s) are highly emphasized. • Fails to meet several important criteria by which election methods are judged. (More later.) • There’s an existing ballot initiative. Nathan Herring

  15. IRV Variants • Allow equal ranking of candidates • Mitigates some problems. • Implicit “no one” candidate, or still count “exhausted” ballots. • Neither of these are in Initiative 318 Nathan Herring

  16. Borda • Mechanism • 1st choice gets (n-1) points. • 2nd choice gets (n-2) points, etc. • Is a regimented ranking system. • Easily victim to strategizing. Nathan Herring

  17. Condorcet (Instant Round-Robin) • Mechanism • Candidates are compared pair-wise. • If one candidate won individually over all other candidates, then they win. • Otherwise, there is a “preference cycle”, which must be broken. • A number of mechanisms to do this exist. (See next slide.) • All preferences are considered (not just topmost). • Not fully ranking the candidates might have negative consequences. • How many people are going to give a complete list? Nathan Herring

  18. Condorcet: Breaking cycles Breaking the cycle involves overruling part of the electorate, so how you do it is important: • Plain Condorcet (PC) • Sequential Dropping (SD) • Ranked Pairs (RP), aka Maximize Affirmed Majorities (MAM) • Schwartz Sequential Dropping (SSD) • Cloneproof SSD (CSSD) • Beatpath Winner (BW) Nathan Herring

  19. Type 3: Cardinal Ratings • You rate every candidate. (e.g. 1-10) • Approval is the simple case: (0-1). • Since rating someone < 10 and > 1 is equivalent to “watering down” your vote, the strategy is to vote as in Approval, so this is not a very interesting case. Nathan Herring

  20. Judging Election Methods Good election systems meet a number of criteria that describe how susceptible the system is to strategy, and to a lesser extent, what the logistics are in terms of calculating the results. • Monotonicity Criterion • Condorcet Criterion • Generalized Condorcet Criterion Nathan Herring

  21. Judging Election Methods, cont. • Strategy-Free Criterion • Generalized Strategy-Free Criterion • Strong Defensive Strategy Criterion • Weak Defensive Strategy Criterion • Favorite Betrayal Criterion • Participation Criterion • Summability Criterion Nathan Herring

  22. How do the methods rate? Data from http://www.electionmethods.org/evaluation.htm Nathan Herring

  23. Is there a perfect method? Probably not. Arrow’s impossibility theorem demonstrates that it is impossible to design a social choice function to choose with at least two members among three options in a way that satisfies fairness properties. Nathan Herring

  24. Further Judging How simple is it? Even methods that produce good results if people follow directions don’t work if people cannot or will not follow them. Can grandma fill out a ballot successfully? Will grandma understand it (and the need for election reform) enough to vote to enact it? Nathan Herring

  25. Initiative 318 “The Voters Full Choice Initiative of 2005”

  26. IRV for Washington State • We would adopt conventional IRV as the mechanism for elections for all offices. • Exceptions are for county judges, county races where the charter provides otherwise, and counties which have adopted IRV. • Need to upgrade our voting systems (again). Nathan Herring

  27. No more primary • Candidates give party affiliation. • One party can have multiple candidates. • A party can have one official nominee. • You vote by ranking every candidate in one big general election. Nathan Herring

  28. No Primary: Implications on IRV • If major parties submit multiple candidates, then we can get into the more-than-two-contender area, which IRV doesn’t handle smoothly. Nathan Herring

  29. Saving taxpayers money… …because primaries become unnecessary. What will really happen? • Major parties submit multiple candidates (with possibly one official candidate) -- Parties trusting in IRV to Do The Right Thing. • Major parties submit only one candidate -- Parties taking matters into their own hands. • Coerce members to not submit themselves? Nathan Herring

  30. Choosing Party Nominees No primary; now what? • Caucuses • Democrats doing that already. • Committee -- Nothing preventing a party from choice by committee. • Less need for candidates for nomination to debate topics in front of the public. • Voting the party line is voting for the committee line. Nathan Herring

  31. Summary • IRV not best method, but • it allows third party preferences to be specified, and • it doesn’t have strategy problems for the two-viable-candidate elections • Good for President, but Insurance Commissioner? • it would ready Washington for Condorcet. • Initiative 318 is still in the signature-gathering process. Nathan Herring

  32. Links • http://www.secstate.wa.gov/elections/initiatives/text/i318.aspx • http://www.irvwa.org/ • http://www.electionmethods.org/ • http://approvalvoting.org/ • http://www5.cs.cornell.edu/~andru/civs/ -- Condorcet Internet Voting Service Nathan Herring

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