Distinguished Approval
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Hi all, reposting from reddit (with minor edits) as per an anonymous suggestion.
I really like both approval and STAR. But, here are some common complaints of each:
Approval
- Ballot does not allow enough expressivity
- Bullet voting is likely
- Disadvantages minority groups who share preferences with majority
STAR
- Score ballot is possibly unconstitutional
- 0-5 scale may make for a visually crowded and confusing ballot
- More fine-grained scale leaves more room for weird edge case participation failures, condorcet failures, etc.
I propose distinguished approval. It's basically just 0-2 STAR except both the ranks 1 and 2 are only worth 1 point each. The ballot asks the voter to express, for each candidate, either "some support" or "strong support" (or blank). The two candidates with the most ballots expressing any amount of support proceed to a runoff; the candidate preferred on more ballots wins.
I haven't done any testing, but given how similar it is to both approval and STAR I imagine it will perform similarly to them. Anyway, it allows for more expressivity than approval (even if the runoff is not that relevant, it just feels better to express a favorite). Also, it will probably help bullet voting since voters will be more willing to give 'some' support to their less-preferred candidates. Lastly, the ballot is much simpler and avoids the legal hairiness of score ballots.
Along a similar vein, I'm also curious if I can rip off STAR-PR (aka Allocated Score ) to use this ballot format. An idea I had (different from what's posted on /r/endFPTP) is to treat the candidates with strong support and those with some support as essentially two different ballots. As you lose voting power it is taken from your 'some support' ballot first, so the 'strong support' ballot retains power longer. That is,
For this modification to be clean we have to multiply all votes by 2 to account for the doubled ballot. Now say I strongly support A, somewhat support B,C but hate D. In the first round my ballot gives 2 points to A,B,C and no points to D.
Now if quota to win is 240 points, and B wins with 300 support, then Allocated Score says I need to allocate 240/300 = 0.8 of my voting weight. But just take the weight from the 'some support' votes first! So in the next round my ballot counts for 0.4 A, and 0 for everyone else. In traditional Allocated Score my ballot would have counted 0.2 A, 0.2 C.
Curious to hear thoughts!
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@brozai said in Distinguished Approval:
0-5 scale may make for a visually crowded and confusing ballot
We could get around this with a hand writing reader or with computer voting.
@brozai said in Distinguished Approval:
More fine-grained scale leaves more room for weird edge case participation failures, condorcet failures, etc.
I am not sure that is true. Do you have evidence?
@brozai said in Distinguished Approval:
, it allows for more expressivity than approval
I agree that this is likely preferable to Approval. You are basically building a three level decision tree. IRNR tries to do this on a higher level.
The down side I see is that the strategy to optimize your vote is very complex. Also you loose the utilitarian advantage STAR has before the run off.
@brozai said in Distinguished Approval:
I'm also curious if I can rip off STAR-PR (aka Allocated Score ) to use this ballot format.
I am not sure I understand this method. Can you give a more detailed example with multiple explicit rounds for one ballot?
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@Keith-Edmonds Thanks for the reply. Regarding the edge case failures---I'm also not sure it's true. In fact, I'm pretty sure this system would also fail consistency & participation. However, my intuition tells me that, due to the simpler ballot, such failures would have to be a result of an even more rare and pathological ballot set than they are in STAR.
The main reason I see to support this over STAR is I think a lot of voters have a hard time stomaching that "some votes are worth more." Although I know that's not actually true and the ballots are all equally powerful, nonetheless it's unfortunately how many regular people interpret score ballots.
An example of PR:
100 voters and 5 seats to elect, so quota is 20. Parties are ABCD with infinite clones. I will write bold for strong support, normal for some support, and omit for no support.
Round 1 tallies:
35: AC
30: BD
20: BC
15: ABA (50), B (65), C (55), D (30)
B is elected with a surplus of 45 votes. All BC ballots are exhausted (because they supported the most strongly). No other reweightings
Round 2 tallies:
35: AC
30: BD
15: ABA (50), B(45), C(35), D (30)
A elected with a 30-vote surplus. All AB ballots exhausted. Now the AC ballots have to come up with 5 total votes to allocate split among them, so their total "power" is each reduced to 1 - 5/35 = 6/7. Regular Allocated Score would have in the next round those ballots count for 6/7 of a vote to A and 6/7 of a vote for C. This method instead keeps the support for the strongly approved C "topped up" to a full vote at the expense of support for A. That is, the AC ballots now contribute 1 vote to C and 5/7 of a vote to A.
Round 3 tallies:
35: AC : 6/7 total ballot weight
30: BDA (25), B (30), C (35), D (30)
C elected with a 15-vote surplus. Now we need to reweight the AC again by a factor of 1-20/35 = 3/7, so the total ballot weight becomes 18/49. Now these ballots contribute 36/49 towards C and 0 towards A.
Round 4 tallies:
35: AC : 18/49 total ballot weight
30: BDA (0), B (30), C (~25.7), D (30)
I suppose you can tie break to choose D since it is preferred on more ballots---I don't expect ties to naturally occur. BD ballots rebalanced to 1-20/30 = 1/3 power, and count their votes 2/3 for D and 0 for B.
Round 5 tallies:
35: AC : 18/49 total ballot weight
30: BD : 1/3 total ballot weightA (0), B (0), C (~25.7), D (20)
Elect C.
Reminder of initial ballots:
35: AC
30: BD
20: BC
15: ABFinal results: {B, A, C, D, C}.
The eyeball test tells me this is a pretty reasonable outcome---technically B had more ballots with approval and was the Condorcet winner, but on the other hand C had more strong supporters. I think maybe an advantage of this system is it really benefits fringe parties, because if a core group of supporters all strongly support a minority candidate, they are very likely to get at least one representative.
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@brozai said in Distinguished Approval:
The main reason I see to support this over STAR is I think a lot of voters have a hard time stomaching that "some votes are worth more." Although I know that's not actually true and the ballots are all equally powerful, nonetheless it's unfortunately how many regular people interpret score ballots.
That is the whole point of the run off. All ballots in the end are equally weighted. This separates it from something like STLR which is a modification to Score to make it work as intended. You should talk to @SaraWolk to see if this is actually a common complaint. I doubt it is and she has talked to a lot of people in campaigns.
@brozai said in Distinguished Approval:
Round 3 tallies:
35: AC : 6/7 total ballot weight
30: BD
A (25), B (30), C (35), D (30)hmmmm should A not be 35*6/7=30? If that is just a calculational error then lets move on to the real issues. C is calculated without the surplus handling reduction to ballot weight. I cannot prove it without putting in more time than I have right now but I think this breaks proportionality or at a minimum causes a chance to free ride.
There may be more happening here than I see. A simpler system is to not treat the distinguished and non-distinguished differently in the calculation (ie just use them as approvals) but have the preference used in exhaustion. That system would work but there may be some weird strategy.
All in all this is not a bad idea and as far as I know it is new. My suggestion would be to make an electowiki page and start to try to get people to review it. @Jameson-Quinn would be a good person to ask. I think the strategy to try to beat Allocated Score is a good one since it seems to be the frontrunner. I would look at comparisons between the two.
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@Keith-Edmonds the AC ballots have 6/7 total ballot weight, but instead of being distributed (6/7, 6/7) as in Allocated Score distribute it (5/7, 1) for weak and strong support respectively, and 5/7*35 = 25. One way to look at it is as weights satisfying
strong_support_weight + some_support_weight = 2*total_ballot_weight
strong_support_weight = min(total_ballot_weight, 1)I'll put a page up on electowiki and try to do some simulations against Allocated Score, possibly using your framework I found here! https://github.com/endolith/Keith_Edmonds_vote_sim
I will say if you just use the ballots as approvals (and don't treat the levels of support differently) then there is no longer any incentive to strongly support a candidate---it doesn't make them more likely to get elected and you just open yourself up to getting exhausted sooner.
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@brozai said in Distinguished Approval:
he AC ballots have 6/7 total ballot weight, but instead of being distributed (6/7, 6/7) as in Allocated Score distribute it (5/7, 1) for weak and strong support respectively,
Does this not break the independence from clones? How would it work in a case where the person supported 3 people (2 weak one strong)? It seems that the more weak support you have the more you have the ability to keep your ballot weight full for your strong support. If it is just one ballot weight for strong and one ballot weight for weak then that might work. You need to think about conservation of vote weight when you do arithmetic like this. When I invented SSS I had do come up with the concept of Vote Unitarity. Of course there are many ways to do this. For example when RRV was invented Warren did not pay attention to the need for such a thing. I later invented SDV to do what RRV does but with a further constraint to hold something constant.
@brozai said in Distinguished Approval:
I'll put a page up on electowiki and try to do some simulations against Allocated Score, possibly using your framework I found here!
If you write python I would suggest putting some code on the electowiki page. I have started doing this to make sure there is no ambiguity. If you follow the conventions I use in the votesim code then it will be the same as my examples on electowiki
@brozai said in Distinguished Approval:
I will say if you just use the ballots as approvals (and don't treat the levels of support differently) then there is no longer any incentive to strongly support a candidate---it doesn't make them more likely to get elected and you just open yourself up to getting exhausted sooner.
Yes, that is correct. So I guess that would be a bad system. But this is sort of tied into what I was saying. You need to keep your counting, exhaustion, etcetera consistent. If not there will be issues.
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Yes, one ballot weight for strong support and one ballot weight for weak support. I did some simulations with 10 winners, 0-2 score, 15000 voters. The PR method as written seems not worth pursuing. I compared to Sequential Monroe and Allocated Score---for my method the equity result are better (less polarization of winners, smaller utility & score deviation), and it also has a significant advantage in average unsatisfied utility. However, basically all the other metrics are worse (avg utility, percent total unsatisfied, etc).
I still like the ballot format and single-winner method, but I think this extension to PR is kind of broken.
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Glad you found my code accessible enough to edit. Changing it from a [0,5] may have been tricky since I might have assumed that in a few places. Anyway, there is a trade off between the two groups of metrics. We saw this a lot and eventually decided Allocated score was a good balance. If you do not think the PR method is worth perusing then good. There is enough out there already and getting alignment on allocated score was not easy.
As for the single winner method you could look into the VSE simulation Jameson did. I would also be interested in seeing how STLR does so if you decide to get into that code it would be great if you could add that.
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@Keith-Edmonds Allocated Score seems like a quite a nice method. I've now simulated a bunch of different modifications I came up with & attempts to beat it, and I don't think I could say that any of them are objectively better---seems like there are indeed unavoidable tradeoffs in those metrics.
When I have time I will check out the VSE code.
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@brozai Bear in mind that this was one of the systems used to choose Allocated Score so getting the same result is not a surprise. Also, SSS performed equivalently from my recollection. Allocated Score was chosen because there was some intuition that it was better than SSS in terms of strategy.