initiative 318 (irv) & election methods

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

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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. - PowerPoint PPT Presentation

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Page 1: Initiative 318 (IRV) & Election Methods

Initiative 318 (IRV)& Election MethodsInitiative 318 (IRV)& Election Methods

A presentation of issues addressed by Washington State Initiative 318 and a

discussion of possible alternatives.

A presentation of issues addressed by Washington State Initiative 318 and a

discussion of possible alternatives.

Page 2: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 22

AbstractAbstract

• 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?

• 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?

Page 3: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 33

GlossaryGlossaryStrategic 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.

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.

Page 4: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 44

Glossary, continuedGlossary, 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.

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.

Page 5: Initiative 318 (IRV) & Election Methods

Election MethodsElection Methods

Page 6: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 66

What is IRV?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.

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.

Page 7: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 77

DemonstrationDemonstration

http://www.chrisgates.net/irv/

Page 8: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 88

Where is IRV in use?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.

• 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.

Page 9: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 99

Alternative Methods & Types

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

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

Page 10: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 1010

Type 1: “Regular” ballot methods

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.

• These methods employ the ballot we use today, where there are ovals next to candidate names.

• Validation and calculation, however, may change.

Page 11: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 1111

PluralityPlurality

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.

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.

Page 12: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 1212

ApprovalApproval

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.

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.

Page 13: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 1313

Type 2: Ranked ballot methods

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.

• 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.

Page 14: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 1414

Instant Run-off VotingInstant 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.

• 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.

Page 15: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 1515

IRV VariantsIRV 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

• Allow equal ranking of candidates• Mitigates some problems.

• Implicit “no one” candidate, or still count “exhausted” ballots.

• Neither of these are in Initiative 318

Page 16: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 1616

BordaBorda

• Mechanism• 1st choice gets (n-1) points.• 2nd choice gets (n-2) points, etc.

• Is a regimented ranking system.• Easily victim to strategizing.

• Mechanism• 1st choice gets (n-1) points.• 2nd choice gets (n-2) points, etc.

• Is a regimented ranking system.• Easily victim to strategizing.

Page 17: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 1717

Condorcet (Instant Round-Robin)

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?

• 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?

Page 18: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 1818

Condorcet: Breaking cycles

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)

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)

Page 19: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 1919

Type 3: Cardinal Ratings 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.

• 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.

Page 20: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 2020

Judging Election Methods 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

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

Page 21: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 2121

Judging Election Methods, cont.

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

• Strategy-Free Criterion• Generalized Strategy-Free Criterion• Strong Defensive Strategy Criterion• Weak Defensive Strategy Criterion• Favorite Betrayal Criterion• Participation Criterion• Summability Criterion

Page 22: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 2222

How do the methods rate?How do the methods rate?MC

CC GCC

SFC

GSFC

SDSC

WDSC

FBC

PC

SC

Plurality • • •

IRV

Approval • • • • •

Borda • • •

Condorcet

• • • • • • • •Data from http://www.electionmethods.org/evaluation.htm

Page 23: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 2323

Is there a perfect method?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.

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.

Page 24: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 2424

Further JudgingFurther 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?

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?

Page 25: Initiative 318 (IRV) & Election Methods

Initiative 318Initiative 318

“The Voters Full Choice Initiative of 2005”

“The Voters Full Choice Initiative of 2005”

Page 26: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 2626

IRV for Washington StateIRV 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).

• 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).

Page 27: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 2727

No more primaryNo 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.

• 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.

Page 28: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 2828

No Primary: Implications on IRV

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.

• If major parties submit multiple candidates, then we can get into the more-than-two-contender area, which IRV doesn’t handle smoothly.

Page 29: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 2929

Saving taxpayers money…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?

…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?

Page 30: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 3030

Choosing Party NomineesChoosing 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.

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.

Page 31: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 3131

SummarySummary

• 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.

• 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.

Page 32: Initiative 318 (IRV) & Election Methods

Monday, 11/29/2004Monday, 11/29/2004 Nathan HerringNathan Herring 3232

LinksLinks

• 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

• 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