although there’s a lot of interesting elements in there, none of it apply to the voting system I presented in this article.
It is a criticism of exactly the voting method you discuss in the article: majority judgement, invented by Balinksi and Laraki.
Honestly, it just looks like you’re trying to push your own thing by denigrating others.
Pointing out objective facts that Balinksi and Laraki failed to acknowledge is called “science”.
Do you have a personal acquaintance with them or something? ’Cause their book is just fine.
Clearly it is not fine, because it fails to address major problems pointed out in my link.
A few paragraph later, I can read:
“Here’s a disturbing example created by Rob Lanphier in 1998. In this 99-voter election with 0–100 score range (four candidates A,B,C,D), B wins under the Balinski-Laraki voting method because B’s median is 51 versus A’s 50:”
Majority Judgement doesn’t use a 0–100 score range, and this is precisely meant to avoid this kind of cases, because the smaller is the range the less room there is for this kind of oddities. (That’s explained in their book, btw)
The criticism cited there is from 1998, a full eight years before majority judgement was invented. It’s a general criticism of median based score voting. The scale doesn’t change anything. Here’s the same example with (what is effectively) the 0–5 scale used by majority judgement.
#voters their vote
49 A=5 B=3 C=0 D=0
1 A=2 B=3 C=5 D=0
49 A=2 B=0 C=0 D=5
99 of 100 voters prefer A to B by a 2 point margin, yet B has a median of 3 while A has a median of 2, and thus B wins.
Why did you take the flaw of another hypothetical voting system, and attribute its to Majority Judgement?
I didn’t. You were just confused.
- Do you have any comparative method proving that “majority judgment is […] extremely vulnerable to tactical voting”, or am I supposed to be convinced by a blurred picture & falsified (unrealistic) edge cases?
Read the article. It explained this:
Considering the cases, in a tight 2-way race with median-based range voting about 50% of the voters have zero incentive to strategize and 50% have incentive.
B&L seem to think that therefore, there will be lots of honest voting. However a different way to look at it is: no voter in this median-based range voting Bush-Gore scenario is hurt by strategizing, but 50% of them are hurt by not strategizing. And it cannot be entirely clear a priori to any voter which kind she is.
Furthermore, that was only thinking about the effect of one voter altering her vote in isolation. If many voters do so, their effects synergize to move the median, which means that somebody who “has no incentive” actually would have incentive once the other strategizers (those who originally had incentive) get done moving it. The more it moves, the more voters have incentive to move it. E.g, consider the situation when the societal median scores have moved to Gore=8.6 and Bush=0.4, and then you as a typical slightly Gore-favoring voter, would then have incentive to exaggerate your scores to 9 and 0 to increase Gore’s win even more, even if originally you had no incentive because originally your vote-alteration could not have altered Bush’s and Gore’s medians. So really, more than 50% of the voters have incentive, and this keeps snowballing until 100% of the Gore>Bush voters will be incentivezed to strategize and the medians move all the way to 9 and 0.
So in view of the synergization and/or the incomplete knowledge effects, everybody would want to strategize, i.e. vote dishonestly — exactly the opposite of B&L’s goal!
The obvious flaw in B&L’s thinking is that they imagine voters only being strategic if the strategy is going to pay off. But that’s not how strategy works! Strategy is about an expected value calculation. For instance, exit polls show about 90% of Green Party supporters vote for someone else, mostly for the Democrat. They do not know that their vote for Green will “spoil” the election (changing it from Democrat to Republican). They simply make a probabilistic assessment: that voting Democrat is more likely to change the winner from Republican to Democrat than to change the winner from Green to Democrat. That Balinski and Laraki fail to understand this is astonishing. But it gets worse.
What happens about strategy in real life?
When we actually look at real-world data from humans using average-based and median-based range voting, what do we find? In all the cases I am aware of so far, the voting seems similar and the election outcomes seem similar. For example, in B&L’s own data set of 1752 voters from France 2007 there obviously was a huge amount of strategic voting going on since by far the most popular score was “zero” — which also is exactly what happened in every (average-based) range voting study I am aware of, including our own, see e.g.
So claims the voters will not feel incentivized to exaggerate, were simply wrong in real life.
On the other hand, there also was a lot of honesty going on since intermediate scores were very popular. Which also is exactly what happened in every average-based range voting study I am aware of, including our own. The same finish-order 1.Bayrou, 2.Royal, 3.Sarkozy, happened with both median-based and average-based 6-level range voting in Orsay France 2007… except when Balinski & Laraki corrected their ballots for geographic biases (their votes came only from Orsay, not all France) it appears that Sarkozy wins (which was clearly worse).
So, while I admit this has not been a maximally-careful examination of election data, I fail to see any noticeable difference in voter behavior with median- versus mean-based range voting — or to the extent there was one, MJ was, in Balinski & Laraki’s own France-2007 study, worse for France! Also in an apparently very large majority of real-world cases it seems both procedures elect the same winner.
So in terms of theory, and computer simulation results, and real world experimental data, MJ just falls on its face.
Don’t you think there’s a weird paradox, when frontally accusing your peers to be dishonest while using such methods at the same time?
You mistakenly thought that example didn’t apply to MJ, and now you’re calling me dishonest because you couldn’t be bothered to take sixty seconds to think through the math?
For the record, Balinski & Laraki acknowledged the limits of their system, as finding a perfect ruleset is simply impossible.
No they do not. Their underlying claims about strategy resistance are pure nonsense.
Any voting system breaks at the edge, but Majority Judgement pushes that edge further than other solutions.
Utterly false. We see from voter satisfaction efficiency (VSE) calculations that majority judgement performs quite poorly with any mixture of strategic or honest voters.
A vastly superior alternative is STAR voting. Just take the two candidates with the most total points, a pit them head to head in an “automatic runoff” based on the scores the voters gave. Extremely simple and transparent, and much better than the hopelessly flawed majority judgement.