[EM] Does IRV elect "majority winners?"

[Dave Ketchum]

On Mon, 05 Jan 2009 00:19:29 -0500 Abd ul-Rahman Lomax wrote:
> At 10:28 PM 1/4/2009, Dave Ketchum wrote:
> 
>> On Sun, 04 Jan 2009 16:16:14 -0500 Abd ul-Rahman Lomax wrote:
>>
>>>
>>> Perhaps. Perhaps not. That can be a *lot* of preparation, and people 
>>> are busy, many don't already, find time for voting. Bullet voting is 
>>> simple, it can be relatively easy to know who your favorite is.
>>
>>
>> Agreed that bullet voting is often appropriate.
>>
>> Only occasional elections provide reason for some voters to do more 
>> ranking.
> 
> 
> And only certain voters. It's relatively uncommon that there are more 
> than two frontrunners, and most voters know who they are. Under those 
> circumstances, the only strong reason not to bullet vote is if you 
> prefer someone other than a frontrunner, and care to express it. The 
> argument for Plurality would be that the system shouldn't be encouraging 
> "useless candidates" to run at all! That is, since vote-for-one usually 
> works, and the only reason it doesn't work (usually, and even this is 
> fairly unusual) is that some silly voters will throw away their vote on 
> a candidate who can't win, why should we respect the unexpressed wishes 
> of those voters? After all, they had their chance! We don't run 
> elections as a popularity contest, i.e., so minor party candidates can 
> brag about how many votes they got....

Your argument for Plurality is empty:
      Letting useless candidates run in Condorcet means less runoffs than 
for Plurality, for voters can vote for both a frontrunner (helping it win), 
and those the voters desire to have counted even if not expected to win.
      Useless candidates can run in Plurality.  Condorcet lets them get 
voted for without, necessarily, disturbing the frontrunner - also, their 
getting counted helps in the rare occasions when they deserve to win.
> 
> *My* point here is that there are some reasons to prefer plurality, we 
> often neglect them completely. Whatever system we try to implement, it's 
> not likely to be stable if it is more work than it's worth. If all the 
> system does is to, nearly always, confirm Plurality results -- and this 
> is the case with IRV in nonpartisan elections -- it is a *huge* waste.

Condorcet certainly costs more for the system than Plurality.  Costs 
bullet-voters nothing - provides a service to whichever voters like to do 
more than bullet vote.
      Actually can be a service to candidates.  Clinton and Obama had to 
try to kill their competitor's campaign for the Democrat nomination they 
could not share.  A similar race in Condorcet would let them both get 
nominated and have a more civilized fight as to which should be ranked 
higher than the other on the ballot.
> 
>> Even if runoffs are possible/expected, it is wise to vote carefully in 
>> the primary to minimize possibility of bad choices getting to the runoff.
>>
>>> And when it isn't easy to know, having trouble deciding between two, 
>>> Open Voting (Approval) allows a simple option: vote for both!
>>
>>
>> What is important is that Condorcet, unlike Approval, permits voting 
>> for both Good and Soso, while indicating that Good is preferred.
> 
> 
> Right. However, with American Preferential Voting (Bucklin), you *can* 
> indicate your preferences. My point is only that equal ranking, if 
> allowed, can be, actually, more expressive.

Bucklin deserves more thought as a competitor to Condorcet.
> 
> Looking over the ballots from Burlington, as I just did, I'm struck by 
> how many voters do seem to imagine that their votes will be counted! 
> Overvotes are more common than I'd expect if they were mere slips. It is 
> very easy for me to imagine that voters think that if they vote for more 
> than one candidate in one of the ranks, why, the votes will be counted, 
> they are merely saying that, for first preference, they prefer either 
> the Progressive or the Democrat, or some other combination. The fact is 
> that if such votes were counted, they'd make sense, even in IRV. 
> (Allowing equal ranking turns IRV into a much better system than without 
> it.)

How do you count equal ranking in IRV?  If I vote X>A=B>Y, A and B become 
visible to the counters at the same time - what does this do to deciding 
what candidate is next to mark lost?
> 
> Those concerned about Later-No-Harm can simply avoid equal ranking!
> 
>>> If any Condorcet method is used, it should allow equal ranking, 
>>> because this *allows* more sincere voting, in fact.
>>
>>
>> AGREED that equal ranking should be permitted.
> 
> 
> Permitting it with Plurality turns Plurality into a far better system, 
> with no cost. Bucklin is very much like Open Voting (i.e., plurality 
> with equal ranking allowed, i.e., Approval) except that it is possible 
> for the voter to rank so that votes are counted in rounds. The original 
> Bucklin only allowed multiple votes in the third rank, but I don't see 
> any reason to *prohibit it* -- i.e., discard ballots that equal rank -- 
> in the first two ranks.

Approval, Plurality and IRV are distractions from need to pick a live 
destination.  I see need to compare, more carefully, Condorcet vs Range vs 
Bucklin.
> 
> It makes one less reason to discard and not count a vote....
> 
> In the Burlington election, there were 77 "blank" ballots, if we can 
> believe the images. I suspect that, in fact, some of these weren't 
> blank, but that they had no vote in the first rank. Another technical 
> reason to discard a ballot. A voter thinks, "I really don't like any of 
> these guys much, so I'll just leave the first preference blank -- not 
> realizing that, probably, by the rules, the ballot won't be counted at 
> all." IRV is *complicated.*
> 
> On a Bucklin ballot, I'd argue, abstaining from the first rank shouldn't 
> cause later ranked votes not to be counted. (And I'd argue that there is 
> no reason in IRV to not count ballots with a vote in second rank, but 
> none if first. The intended meaning is reasonably clear.)
> 
>>> However, majority vote and avoidance of all runoffs are two 
>>> incompatible goals. So the question is, how important is it that a 
>>> majority of those voting support the winner?
>>
>>
>> The CW has been compared with EACH other candidate, and found better 
>> liked in every case.  However this does not guarantee a majority, 
>> since voters are not each required to rank all candidates.
> 
> 
> That's right. And, in fact, it could only be a small minority who so 
> voted, i.e., that the winner was "better liked." Majority requirements 
> *require* that the electorate actually consider and accept or reject a 
> winner.

A "small minority" cannot win in Condorcet, except for the tortured case of 
a zillion candidates with at most a small minority voting for any one.

I am still trying to promote series thought as to need for a majority for 
other than Plurality or Approval.
> 
>> When there is a cycle its 3 or more members would each be CW if compared
>> only with non-cycle members.  For this I claim near-ties since their
>> strengths overlap.
>>
>>> I'd say it is a bare minimum! We have a defective democracy when we 
>>> elect with other than a majority, either of voters directly, or 
>>> through chosen representatives. Where representation is involved, we 
>>> have a defective democracy even with a majority!
>>
>>
>> Plurality NEEDS majority for, if top candidate gets less, another 
>> could deserve the win and these voters cannot completely express their 
>> desires in their votes.
> 
> 
> All methods need majorities to satisfy basic democratic norms. 
> Democratic process, in deliberative bodies, generally avoids 
> multiple-choice questions; where such questions are allowed, as in 
> elections, a majority is required, just as it is with bivalued (Yes/No)
> questions.

Go to RRONR and you see demand for a supermajority for some cases.  I still 
question actual need for a majority for all election methods (other than 
Plurality, which has true need).
> 
>> Condorcet has less need, for its voters can rank all the candidates 
>> they approve of.
> 
> 
> Less need, perhaps. It's possible that the Condorcet winner is a winner 
> by a majority over all other candidates. Advanced voting systems, in 
> general, can be used as devices to avoid unnecessary runoffs.

Try:
      77A; 76B; 75C; 74blank
These voters like bullet voting and none ranks any competitor of their 
first choice (though they could have ranked more if they approved of any). 
  Why not let A win?  If you insist on a runoff, who deserves to be on that 
ballot?
      77A; 77B
Here I recommend the rules say "flip a coin" - and anyone who objects to 
that should get to finance the runoff.
> 
> But Condorcet methods without some test of acceptance can fail rather 
> badly. It could be that the majority would reject the Condorcet winner, 
> given a choice of electing the person or running the whole election 
> over, and the only reason it appeared that this was the Condorcet winner 
> was that, say, voters fully ranked, and some of those who formed the 
> majority in some of the wins were actually saying that this was the 
> second-worst candidate, which could be pretty bad....

I do not understand "fail" here - Condorcet permits ranking multiple 
candidates by any voter who chooses to.

I choke on any encouragement of "fully ranked".  For example, ranking the 
next to last is usually not worth the pain for it affects only the 
relationship between the last two.
> 
> If you are going to use pure ranking, with a single ballot, Cordorcet is 
> king, so to speak. But that's an artificial limitation.
> 
> I do agree that if a better method is used (like Range or Score Voting), 
> a Condorcet test should be used to ensure that the Condorcet winner 
> isn't unconciously rejected. A runoff is needed to test this. If we have 
> a conflict between a Range winner and a Condorcet winner, what has 
> happened is that there may be a majority -- or a plurality -- with a 
> weak preference, against a minority with a strong preference. Social 
> utility theory would say that the Range winner is better; but the votes 
> imply that a majority would reject that winner in favor of the Condorcet 
> winner. For reasons I've described many times, I claim that a genuine 
> Range winner will prevail in a runoff, and that this would be the best 
> result. But occasionally, that would not happen, and the Condorcet 
> winner would prevail; what might be happening here is that the majority 
> is saying, "No, we do *not* want to give up our right of decision as a 
> majority, we don't accept the Range results as valid, or, for whatever 
> reason, we, in the majority, don't want to make the sacrifice."

Ugh!  How do you get valid multiple method results without imposing some 
kind of load on the voters?
> 
> And that is their right.
> 
> But it won't happen very often....
> 
>> Therefore I recommend careful thought as to when runoffs may be worth 
>> their expense.
> 
> 
> Sure. Little work has been done on this. Some systems require a runoff 
> when the margin is less than a certain percentage. That makes sense.... 
> Ideally, whatever system is used would predict what would happen in a 
> runoff, with reasonable accuracy, and then hold a real runoff only when 
> the possibility of a different result is significant.
> 
> Looking at the Burlington results, even though Bob Kiss did not gain a 
> majority of the votes, as reported by IRV, it's highly likely that he'd 
> win a real runoff against the runner-up, Miller, his margin was large 
> enough and there is no particular reason for it to disappear. In fact, 
> if we look at the second-choice votes, both he and Miller gained a 
> majority of first and second-choice votes. My guess is that Bucklin 
> would have returned a majority victory for him. IRV concealed a lot of 
> votes for Kiss underneath votes for Miller, and a lot of votes for 
> Miller underneath votes for Kiss. More Miller votes were concealed than 
> Kiss votes: the Kiss supporters were less likely to vote for Miller in 
> second place than the reverse.
> 
> Were it Bucklin, *some* voters would have truncated, not voting for the 
> other frontrunner. But, my guess, most wouldn't have truncated, and so 
> Kiss would have still obtained a majority. (There was a lot of 
> truncation, bullet voting, even with IRV.)
> 
> In the other direction, there were many voters, far more than I 
> expected, who *fully ranked,* so fully that they essentially voted for 
> every candidate against any write-in. (There was even one voter who 
> ranked all the candidates *and* wrote in a name in the last place, 
> overvoting that position.) Imagine what would happen if there was a 
> serious write-in candidacy in such an environment. These full-ranking 
> voters may have just voted for their worst nightmare, thinking that by 
> ranking this candidate "last," they were maximally voting against him or 
> her.
> 
> In this sense, three-rank IRV might be better....
> 
> (Burlington had five candidates on the ballot plus one write-in slot, 
> hence, because apparently they wanted to allow full ranking, they 
> allowed five ranks. The idea is that bottom rank is unexpressed. So you 
> could vote for your total favorite in first rank, say, then for the best 
> four of the other five candidates. But many voters seemed to think that 
> the fifth rank was the bottom, and it's apparent that many tried to use 
> burial strategy, bottom ranking the perceived competitor, while giving a 
> higher rank to a total joke candidate who they would probably be 
> horrified to elect. On the other hand, surprisingly many voters *wrote 
> in* a name in the fifth rank.)
> 
>> BTW - cost of ballot support for complete ranking can tempt limits on 
>> Condorcet ranking.  How bad should we complain if offered 3 as in RCV?
> 
Three seems like a good minimum, with cost vs voter desires controlling 
whether more get implemented.
> 
> It's not the worst problem. Center squeeze is the worst problem.
-- 
  davek at clarityconnect.com    people.clarityconnect.com/webpages3/davek
  Dave Ketchum   108 Halstead Ave, Owego, NY  13827-1708   607-687-5026
            Do to no one what you would not want done to you.
                  If you want peace, work for justice.