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IRV versus Condorcet methods

Blahface

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I am really getting annoyed by attempts from IRV advocates trying to make rank choice voting synonymous with instant runoff voting. I'm generally not in favor of rank choice methods, but if you have to choose one, why in the world would you not want a Condorcet method such as Black's method (using a Borda count to break cycle)? It is arguably easier to explain, it is easier to tabulate, and it provides a more accurate winner.

Can anyone think of a reason to promote IRV ahead of a Condorcet method?
 
I personally disagree that Condorcet is easier to explain. Looking at a spreadsheet of Condorcet pairings is very confusing. It is much easier for me to see the loser in each round of IRV.

I don't know how you determine which winner is "more accurate." Every voting strategy accomplishes exactly what it tries to accomplish.

Edit:

I also read somewhere on the internet (I don't have a source and I don't think they did either) that in actual competitive elections (as opposed to theoretical ones) IRV actually elects the true Condorcet winner slightly more often than the Condorcet voting method does. One reason for this is the way real voters choose to use what they know about the system to vote strategically and against their actual preferences. Another reason is that Condorcet is vulnerable to spoiler candidates with little core support but mediocre broad support while the opposite vulnerability in IRV, "center squeeze candidates" with big core support and little broad support don't occur in actual campaigns very often.
 
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I personally disagree that Condorcet is easier to explain. Looking at a spreadsheet of Condorcet pairings is very confusing. It is much easier for me to see the loser in each round of IRV.

What I meant was that it is easier to explain to regular people who haven't heard about it. If you just say “You rank the candidates and the candidate who beats all the other candidates in one-on-one comparisons wins,” I think most people would get it. It would be a little more difficult explaining the tie breaker method depending on which one is being used.

It also isn't that difficult to just explain the results. If you are going to explain the results on a newscast, you could just talk about the winners victories against the top competitors.

I don't know how you determine which winner is "more accurate." Every voting strategy accomplishes exactly what it tries to accomplish.

I'd think that the purpose of an election is get the candidate that best represents the people. You can either define this as the one that either elects the Condorcet winner or the one that provides the most voter utility. The Condorcet method outperforms IRV in both areas.

I also read somewhere on the internet (I don't have a source and I don't think they did either) that in actual competitive elections (as opposed to theoretical ones) IRV actually elects the true Condorcet winner slightly more often than the Condorcet voting method does. One reason for this is the way real voters choose to use what they know about the system to vote strategically and against their actual preferences. Another reason is that Condorcet is vulnerable to spoiler candidates with little core support but mediocre broad support while the opposite vulnerability in IRV, "center squeeze candidates" with big core support and little broad support don't occur in actual campaigns very often.

I'd really like to know how it was determined that IRV is more Condorcet than Condorcet. I'm not aware of any meaningful elections that used a Condorcet method with regular voters. Any strategy that voters would take on would just be speculative. That being said though, it is my opinion that among regular voters, there wouldn't be any significant strategic voting in which the voters are purposely trying create a cycle. My fear with Condorcet is that people would just bury the candidate they hate the most without knowing anything about the candidates they ranked above him and accidentally elect someone who they know nothing about. I don't even think this would be too likely though.

We've already seen the “center squeeze” happen in Burlington Vermont in 2009. There were also some exit polls done on the 2007 French Presidential election with different voting methods. Under IRV, Sarkozy was still the winner even though Bayrou was pretty clearly the more favored candidate.

We've also seen the “Center Squeeze” in the US primaries which behave similar to the early rounds in IRV. This has been mainly from the Republicans who seem to be more likely to vote their conscience and elect non-viable tea party candidates to the general like Christine O'Donnell and Sharon Angle. I'm somewhat worried that Bernie Sanders may fill this spoiler role in 2016, but I dislike Hilary enough to take that risk in the primary.
 
I still think your brief explanation of "the candidate who beats all the other candidates in one to one comparisons wins" is still confusing because it is incomplete regarding ties/circle situations.

As for which candidate best represents the people... That is a problem of definition. Technically first past the post voting systems elect candidates with the biggest core support compared to their competitors. This is a perfectly valid way to select a candidate who represents what "more" people want. Of course we both know what is wrong with this, but my point is that it satisfies a satisfactory definition of "representing the people."

Regarding how to abuse the condorcet voting system to elect non-condorcet winners, it is really about evaluating the competition and putting not your least desireable candidate on the bottom but rather the candidate you percieve to be the biggest threat to your most prefered candidate. When you do that, your biggest threat candidate who may be the actual condorcet winner(by honest preference) starts to lose more pairings to candidates who actually have very little core support or even much broad support.

But because in all ranked voting elections nobody ranks their most preferred candidate anywhere except for number 1 those extraneous candidates with little core support are usually eliminated in the first several rounds of IRV leaving the serious contenders to battle it out in the later rounds.
 
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