User:RalphInOttawa/Standard Vote: Difference between revisions

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'''Standard Vote does IRV first (2 or 3 times) and pairwise comparisons second (only between runoff winners).'''
'''Standard Vote''' (abbreviated as '''SV''') is an election vote-counting method that chooses a single candidate by using ranked ballots and the sequential elimination of lowest counting candidates in two or three runoffs. Thereby addressing the unfairness of a single runoff voting system.


Standard Vote (abbreviated as SV) is an election vote-counting method that chooses a single candidate by using ranked ballots and the sequential elimination of lowest counting candidates in two or three runoffs. This addition to IRV addresses the unfairness inherent in a single runoff voting system, by identifying when the runner-up has a spoiler effect on the election and doing something about it.
This method modifies [[Instant-Runoff Voting|instant runoff voting]] (IRV) by adding a second and possibly a third runoff with [[later-no-harm]] safeguards for runoff winners. It further modifies simple IRV by allowing the voter to mark more than one candidate at the same ranking level. These additions claim to improve on simple IRV by: more fairly counting a voter's honest opinion, making this system more monotonic ([[Monotonicity]]), reducing the failure rate for the [[Independence of irrelevant alternatives|Independence of Irrelevant Alternatives]] (IIA), eliminating [[Center-squeeze]], and making the practice of [[Favorite Betrayal]] unnecessary.


This method modifies Instant Runoff Voting (IRV) by adding a second and possibly a third runoff with later-no-harm safeguards for runoff winners. It further modifies simple IRV by allowing the voter to mark more than one candidate at the same ranking level. These additions improve on simple IRV by: allowing voters to give a full and honest opinion, making this system more monotonic (Monotonicity), reducing the failure rate for the Independence of Irrelevant Alternatives (IIA), eliminating Center-squeeze, and making the practice of Favorite Betrayal unnecessary.
== Description ==
Voters rank the candidates using as many ranking levels as there are candidates, or to a limit as specified by the electing authority. Four levels is manually countable and a reasonable compromise as few voters will remember, nor be happy with, whomever their fifth and additional down ballot choices were.


This method begins with a first runoff. Candidates are eliminated one at a time in each runoff, with the vote counts of the final two candidates compared (effectively pairwise) to identify a winner and a runner-up. The method continues with a second runoff, in which the first runoff's runner-up is immediately withdrawn. The voter's preferences trapped behind/under the runner-up are now countable like those of other voters whose first preference has lost. This identifies a second runoff winner. If the first winner repeats as the second winner, they are elected and the election is over.


'''Description'''
If no one is elected, a pairwise comparison is made of the first and second winners. The first winner will be elected if the second winner can do no better than a tie. Failing that, a third runoff occurs in which the first runoff's winner is immediately withdrawn. The votes previously trapped behind/under the first winner in both runoffs are now countable like those of other voters whose first preference has lost. This identifies a third winner. If the second winner repeats as the third winner, they are elected and the election is over.


Voters rank the candidates using as many ranking levels as there are candidates, or to a limit as specified by the electing authority. The Google spreadsheet demonstrator (link below) has five levels of ranking which makes it possible to compare apples to apples with some other voting systems.
If no one has been elected, a pairwise comparison is made of the second and third winners. The second winner will be elected if the third winner can do no better than a tie. Failing all of the above, the third winner is compared pairwise with the first winner. The third winner will be elected if they beat the first winner. Finally, with no one elected, the result is a paradoxical tie between the three runoff winners. One of them will be elected by "random draw".


Ballots are collected and recorded. Equal rankings on ballots are turned into ranked choices based on a random ordering of candidates. This is followed by the first runoff. Candidates are eliminated one at a time in each runoff, with the vote counts of the final two candidates compared (effectively pairwise) to identify a winner and a runner-up. The method continues with a second runoff, in which the first runoff's runner-up is immediately withdrawn. The voter's preferences trapped behind/under the runner-up are now countable like those of other voters whose first preference has lost. This identifies a second runoff winner. If the first winner repeats as the second winner, the decision is made to elect the first/second winner.
== Tie breakers ==
[[Random Voter Hierarchy]] (RVH) is used for each "random draw". Ideally these values are determined at the "instant" the counting begins, giving candidates and voters nothing to apply a strategy to. If two or more candidates have the same rank on any number of ballots, this tie is re-ranked by "random draw" en masse. All votes will fall the same way throughout all elimination rounds in all runoffs (all occurrences of A=B will either all count as A>B or all count as B>A). All ties encountered during elimination rounds will be decided by a different "random draw". This will cause ties between candidates to be decided in the same candidate's favor throughout all elimination rounds. In pairwise ties between runoff winners, the earlier winner's count takes precedence over a subsequent winner's count. In the scenario of the paradoxical tie, the candidate to be elected will be decided by yet another different "random draw".


If no decision, a pairwise comparison is made of the first and second winners. The first winner will be elected if the second winner can do no better than a tie. Failing that, a third runoff occurs in which the first runoff's winner is immediately withdrawn, giving supporters of the first winner the same fairness that supporters of the runner-up received in the second runoff. This identifies a third winner. If the second winner repeats as the third winner, the decision is made to elect the second/third winner.
== Examples ==

The paradoxical tie. Each candidate has an equal claim to be elected. In this example, one of the three candidates will be elected by "random draw".
If no decision, a pairwise comparison is made of the second and third winners. If the third winner can do no better than tie the second winner, a decision is made to elect the second winner. If no decision, the third winner is compared pairwise with the first winner. If the third winner beats the first winner, the decision is made to elect the third winner. Finally, with no decision made, the result is a paradoxical tie between the three runoff winners. A decision is made to elect one of the three runoff winners by a "random draw".


'''Tie breakers'''

Random Voter Hierarchy (RVH) is used for each "random draw". Ideally these values are determined at the "instant" the counting begins, giving candidates and voters nothing to apply a strategy to. If two or more candidates have the same rank on any number of ballots, this tie is re-ranked by "random draw" en masse (all occurrences of A=B will either all count as A>B or all count as B>A). Ties encountered during elimination rounds will be decided by a second "random draw" applied in all elimination rounds. In comparing runoff winners, in the event of a tie, the earlier winner's count takes precedence over a subsequent winner's count. When thre's a paradoxical tie, the candidate to be elected will be decided using the third "random draw".


'''Proof of concept'''

Here's a shared link to a spreadsheet demonstrator (10 candidates, 1-5 picks, 200 voting rows. Note: you need to be signed on to a Google Account).

https://docs.google.com/spreadsheets/d/1UR7yJyN3XYszE0LYRe9J-RE1YbEdOHvuq1X2-LOaEac/edit#gid=664199959


As of April 2024 I've made an Excel workbook for Excel users (10 candidates, 1-5 picks and 50 voting rows):

https://onedrive.live.com/edit?id=7D93452D5E5AF617!sd3058ae1ff854d99ab8d1d5761a980c1&resid=7D93452D5E5AF617!sd3058ae1ff854d99ab8d1d5761a980c1&cid=7d93452d5e5af617&ithint=file%2Cxlsx&redeem=aHR0cHM6Ly8xZHJ2Lm1zL3gvYy83ZDkzNDUyZDVlNWFmNjE3L0VlR0tCZE9GXzVsTnE0MGRWMkdwZ01FQnZrZnRMUm9EdXNCMEhybVhzaFpaT1E_ZT0wS0NmRXI&migratedtospo=true&wdo=2

For those who can’t access these spreadsheets, here are short descriptions of SV's eleven step process.

1: Create 3 random draws of alternatives for use in steps 2, 3, 4, 7 and 11.

2: Convert equal ranking on ballots to ranked choices (using the 1st random draw to order equally ranked choices).

3: Execute a “normal” IRV runoff to identify the 1st winner and a runner-up (2nd random draw breaks ties).

4: Execute a 2nd IRV runoff without the runner-up from step 3, identifying a 2nd winner (2nd random draw breaks ties).

5: If the same alternative wins both runoffs, elect that alternative.

6: If the 1st winner does not lose to the 2nd winner, one on one, elect the 1st winner.

7: Execute a 3rd runoff without the 1st winner from step 3, identifying a 3rd winner (2nd random draw breaks ties).

8: If the same alternative wins the 2nd and 3rd runoffs, elect that alternative.

9: If the 2nd winner does not lose to the 3rd winner, one on one, elect the 2nd winner.

10: If the 3rd winner beats the 1st winner, one on one, elect the 3rd winner.

11: Elect one of the three runoff winners (3rd random draw to decide).

'''Examples comparing SV to IRV'''

This example shows a paradoxical tie. To be fair, SV gives each candidate an equal chance of election.


4 A>B
4 A>B
Line 24: Line 67:
2 C>A
2 C>A


IRV elects A. SV decides who wins a three way tie (step 11).
The next example shows how Standard Vote does not suffer from center-squeeze. Candidate C is elected.


The next example shows how Standard Vote does not suffer from center-squeeze.


4 A>C
4 A>C
Line 32: Line 78:
2 C
2 C


IRV elects A. SV elects Candidate C (step 8).
The following example demonstrates that favorite betrayal is not necessary. C wins. 2 A>C turning into 2 C>A is not needed.


The following example demonstrates that favorite betrayal is not necessary.


4 A>C
4 A>C
Line 40: Line 89:
2 C>B
2 C>B


IRV elects B. SV elects C (step 8). No need to turn 2 A>C into 2 C>A.
The 4th example illustrates the system doing a lot better than IRV at not failing to be monotonic


The 4th example illustrates the system doing a lot better than IRV at not failing monotonicity.


8 A
8 A
Line 48: Line 100:
4 C>B
4 C>B


IRV and SV elect B.
IRV elects B, but when 2 supporters of A change their votes to C (favorite betrayal), A wins. In this improved version of IRV, the original result still elects B, and the new result is a three way tie that will be decided by random draw. Still not monotonic but not the guaranteed win by A. However, the same result is achieved without betrayal, and not failing monotonicity, if those 2 voters had simply added C as a preference, casting A>C.


When 2 supporters of A change their votes to C (favorite betrayal):

6 A

'''2 C'''

5 B>A

4 C>B

IRV elects A. SV decides who wins the three way tie (step 11).



Using SV, the same result can be produced by simply having the 2 supporters of A add C to their ballots.

6 A

'''2 A>C'''

5 B>A

4 C>B

IRV elects B. SV decides who wins in the three way tie (step 11).

Latest revision as of 20:00, 25 April 2024

Standard Vote does IRV first (2 or 3 times) and pairwise comparisons second (only between runoff winners).

Standard Vote (abbreviated as SV) is an election vote-counting method that chooses a single candidate by using ranked ballots and the sequential elimination of lowest counting candidates in two or three runoffs. This addition to IRV addresses the unfairness inherent in a single runoff voting system, by identifying when the runner-up has a spoiler effect on the election and doing something about it.

This method modifies Instant Runoff Voting (IRV) by adding a second and possibly a third runoff with later-no-harm safeguards for runoff winners. It further modifies simple IRV by allowing the voter to mark more than one candidate at the same ranking level. These additions improve on simple IRV by: allowing voters to give a full and honest opinion, making this system more monotonic (Monotonicity), reducing the failure rate for the Independence of Irrelevant Alternatives (IIA), eliminating Center-squeeze, and making the practice of Favorite Betrayal unnecessary.


Description

Voters rank the candidates using as many ranking levels as there are candidates, or to a limit as specified by the electing authority. The Google spreadsheet demonstrator (link below) has five levels of ranking which makes it possible to compare apples to apples with some other voting systems.

Ballots are collected and recorded. Equal rankings on ballots are turned into ranked choices based on a random ordering of candidates. This is followed by the first runoff. Candidates are eliminated one at a time in each runoff, with the vote counts of the final two candidates compared (effectively pairwise) to identify a winner and a runner-up. The method continues with a second runoff, in which the first runoff's runner-up is immediately withdrawn. The voter's preferences trapped behind/under the runner-up are now countable like those of other voters whose first preference has lost. This identifies a second runoff winner. If the first winner repeats as the second winner, the decision is made to elect the first/second winner.

If no decision, a pairwise comparison is made of the first and second winners. The first winner will be elected if the second winner can do no better than a tie. Failing that, a third runoff occurs in which the first runoff's winner is immediately withdrawn, giving supporters of the first winner the same fairness that supporters of the runner-up received in the second runoff. This identifies a third winner. If the second winner repeats as the third winner, the decision is made to elect the second/third winner.

If no decision, a pairwise comparison is made of the second and third winners. If the third winner can do no better than tie the second winner, a decision is made to elect the second winner. If no decision, the third winner is compared pairwise with the first winner. If the third winner beats the first winner, the decision is made to elect the third winner. Finally, with no decision made, the result is a paradoxical tie between the three runoff winners. A decision is made to elect one of the three runoff winners by a "random draw".


Tie breakers

Random Voter Hierarchy (RVH) is used for each "random draw". Ideally these values are determined at the "instant" the counting begins, giving candidates and voters nothing to apply a strategy to. If two or more candidates have the same rank on any number of ballots, this tie is re-ranked by "random draw" en masse (all occurrences of A=B will either all count as A>B or all count as B>A). Ties encountered during elimination rounds will be decided by a second "random draw" applied in all elimination rounds. In comparing runoff winners, in the event of a tie, the earlier winner's count takes precedence over a subsequent winner's count. When thre's a paradoxical tie, the candidate to be elected will be decided using the third "random draw".


Proof of concept

Here's a shared link to a spreadsheet demonstrator (10 candidates, 1-5 picks, 200 voting rows. Note: you need to be signed on to a Google Account).

https://docs.google.com/spreadsheets/d/1UR7yJyN3XYszE0LYRe9J-RE1YbEdOHvuq1X2-LOaEac/edit#gid=664199959


As of April 2024 I've made an Excel workbook for Excel users (10 candidates, 1-5 picks and 50 voting rows):

https://onedrive.live.com/edit?id=7D93452D5E5AF617!sd3058ae1ff854d99ab8d1d5761a980c1&resid=7D93452D5E5AF617!sd3058ae1ff854d99ab8d1d5761a980c1&cid=7d93452d5e5af617&ithint=file%2Cxlsx&redeem=aHR0cHM6Ly8xZHJ2Lm1zL3gvYy83ZDkzNDUyZDVlNWFmNjE3L0VlR0tCZE9GXzVsTnE0MGRWMkdwZ01FQnZrZnRMUm9EdXNCMEhybVhzaFpaT1E_ZT0wS0NmRXI&migratedtospo=true&wdo=2

For those who can’t access these spreadsheets, here are short descriptions of SV's eleven step process.

1: Create 3 random draws of alternatives for use in steps 2, 3, 4, 7 and 11.

2: Convert equal ranking on ballots to ranked choices (using the 1st random draw to order equally ranked choices).

3: Execute a “normal” IRV runoff to identify the 1st winner and a runner-up (2nd random draw breaks ties).

4: Execute a 2nd IRV runoff without the runner-up from step 3, identifying a 2nd winner (2nd random draw breaks ties).

5: If the same alternative wins both runoffs, elect that alternative.

6: If the 1st winner does not lose to the 2nd winner, one on one, elect the 1st winner.

7: Execute a 3rd runoff without the 1st winner from step 3, identifying a 3rd winner (2nd random draw breaks ties).

8: If the same alternative wins the 2nd and 3rd runoffs, elect that alternative.

9: If the 2nd winner does not lose to the 3rd winner, one on one, elect the 2nd winner.

10: If the 3rd winner beats the 1st winner, one on one, elect the 3rd winner.

11: Elect one of the three runoff winners (3rd random draw to decide).

Examples comparing SV to IRV

This example shows a paradoxical tie. To be fair, SV gives each candidate an equal chance of election.

4 A>B

3 B>C

2 C>A

IRV elects A. SV decides who wins a three way tie (step 11).


The next example shows how Standard Vote does not suffer from center-squeeze.

4 A>C

3 B>C

2 C

IRV elects A. SV elects Candidate C (step 8).


The following example demonstrates that favorite betrayal is not necessary.

4 A>C

3 B>C

2 C>B

IRV elects B. SV elects C (step 8). No need to turn 2 A>C into 2 C>A.


The 4th example illustrates the system doing a lot better than IRV at not failing monotonicity.

8 A

5 B>A

4 C>B

IRV and SV elect B.


When 2 supporters of A change their votes to C (favorite betrayal):

6 A

2 C

5 B>A

4 C>B

IRV elects A. SV decides who wins the three way tie (step 11).


Using SV, the same result can be produced by simply having the 2 supporters of A add C to their ballots.

6 A

2 A>C

5 B>A

4 C>B

IRV elects B. SV decides who wins in the three way tie (step 11).