Talk:Instant-runoff voting: Difference between revisions
→Fixing the shortcomings of IRV: new section
(→Does anyone call it IRV any more?: - I'm not inclined to go against the consensus over at English Wikipedia (see w:Instant-runoff voting)) |
(→Fixing the shortcomings of IRV: new section) |
||
Line 14:
:: My point is that AFAICT, none of the English-speaking nations that actually use IRV call it IRV. (update) Australia, NZ, Papua call it Preferential Voting. US & Canada call it RCV. UK calls it Alternative Vote. Ireland & India call it STV. So it can't possibly be correct to say it's "the term which everybody uses". - [[User:Frankie1969|Frankie1969]] ([[User talk:Frankie1969|talk]]) 13:21, 28 September 2021 (UTC)
::: It appears to be called "instant-runoff voting" on English Wikipedia (see [[w:Instant-runoff voting]]). I'm not inclined to go against the consensus over there. -- [[User:RobLa|RobLa]] ([[User talk:RobLa|talk]]) 20:56, 28 September 2021 (UTC)
== Fixing the shortcomings of IRV ==
I would like to fix the shortcomings of IRV. For discussion, I offer an eleven step instant runoff process to do that. Some of the examples on this website are reproduced here to illustrate how an IRV process can do better.
Compromise: regarding the Memphis example.
IRV elects Knoxville, some compromises are suggested to avoid electing Knoxville.
Nashville will be elected when the 42 Memphis>Nashville>Chattanooga>Knoxville voters
flip their votes to Nashville>Memphis>Chattanooga>Knoxville. Alternatively it is
suggested that the 26 Nashville>Chattanooga>Knoxville>Memphis voters flip their votes
to Chattanooga>Nashville>Knoxville>Memphis to elect Chattanooga, again avoiding the
election of Knoxville.
I have Nashville elected in step 8. No need for anyone to compromise.
IRV can fail to pick a good compromise.
38 A>C>B
38 B>C>A
11 C>A>B
13 C>B>A
IRV elects B. I would elect C in step 8.
IRV fails to count the ballots in a way most favorable to the voters.
26 A>B
25 C>B
49 D
IRV elects D. I see a three way tie, and I will elect one of A, B or D in step 11.
IRV is vulnerable to center-squeeze (“the three candidate” example from center-squeeze).
1031 A>B>C
415 B>A>C
446 B>C>A
1108 C>B>A
IRV elects A. I would elect B in step 8. IRV needs to be less vulnerable to
center-squeeze, the center candidate, B in this example, should win.
IRV is vulnerable to favorite betrayal: from the favorite betrayal criterion.
10 A>B>C>D
6 B>A>C>D
5 C>B>A>D
20 D>A>C>B
IRV elects B. I would elect A in step 8. IRV needs to be less vulnerable to favorite
betrayal, voters should not need to change their votes.
IRV gives supporters of A an opportunity to win if they betray their favorite.
2 C>A>B>D
8 A>B>C>D
6 B>A>C>D
5 C>B>A>D
20 D>A>C>B
IRV elects A. I would still elect A, this time in step 5.
Supporters of A should not have to be this sneaky.
Please consider using an eleven step instant runoff process to make IRV more fair.
I have used Google Sheets to create a demonstrator. I'm old and not an expert in anything. But I'm pretty sure it works. I will be very embarrassed if I've made typos in the formulae and the results don't make sense. Point it out and I'll fix it. Here's a link to my spreadsheet:
https://docs.google.com/spreadsheets/d/1D1Aeoy3Y17gcnCyVx6AlGEIYneDidRpqn5a-lClC66I/edit#gid=664199959
--[[User:RalphInOttawa|RalphInOttawa]] ([[User talk:RalphInOttawa|talk]]) 05:00, 2 December 2023 (UTC)
| |||