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Majority score voting: Difference between revisions
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#* ''This finds the candidate with the widest and deepest support.''
Note: Majority score voting was originally called SARA voting, an acronym for the 4 ratings voters
== A few quick scenarios ==
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Now suppose that there are two overall ideological "sides", and the majority "side" is split into two subfactions, each smaller than the full minority "side". This is called the "[[chicken dilemma]]", because many voting systems encourage a "game of chicken" between the two majority subfactions; whichever subfaction cooperates less will win, unless cooperation breaks down entirely and the minority wins. A very closely-balanced chicken dilemma would have 27% for subfaction A, 26% for subfaction B, and 47% for the minority Z; whereas a more typical example might have 31%, 24%, and 45%. In Majority Score, each subfaction should support their candidate, accept the other subfaction's, and reject the minority; while minority voters should support their candidate and reject both subfactions. In this case, the bigger subfaction will win.
Note that A, the bigger of the two subfactions, must necessarily be above the 50-point threshold in step 2, so Z will be safely eliminated. In many cases, B, the smaller subfaction, will fall short of 50 points. This helps explain the rationale for putting that threshold at 50 points.
This is not to say that majority score solves the chicken dilemma 100%. It is still possible for the smaller subfaction B to win if they largely reject the A while the A voters largely accept B. And if both factions largely reject, Z can win. But the key word there is "largely"; unlike the case with [[approval voting]] or [[score voting]], this strategy will not work if it's done by only a few individual voters, but only if one subfaction uses it significantly more than the other. Given that organizing such a coordinated betrayal in secret would be hard, and that doing so openly would invite mutually-destructive retaliation, it seems that majority score voting has a good chance of avoiding this problem.
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It is very rare to have a voting system which can deal with both chicken dilemma and center squeeze. The two situations are very similar, even when voted honestly, and yet the "correct" outcome is different. And under strategic voting in many voting systems, it is very easy for the two different scenarios to lead to identical ballots. Delegated voting systems such as [[SODA voting]] can deal with both; but without that kind of explicit participation in the voting process from the candidates, it is very hard to find a system which deals with both types of scenario better than majority score does.
== As the first round of a two-round system ("
If this system is used as the first round of a two-round runoff, then you want to use it to elect at two finalists in the first round. Thus, run the system twice. The first time, replace "50%" in step 2 with "2/3".
Then, to find the second winner, if the first-time winner got 1/3 or more support, first downweight those ballots as if you'd eliminated enough of them to make up 1/3 of the electorate. Otherwise, discard all of the ballots which supported first-time winner. After downweighting or discarding, re-tally the points and
If all the candidates in the first round got a majority of 0's, then you can still find two finalists as explained above. But the voters have sent a message that none of the candidates are good, so one way to deal with the situation would be to have a rule to allow candidates to transfer their 2-votes to new candidates who were not running in the first round, and if those transfers would have made the new candidates finalists, then add them to the second round along with the two finalists who did best in the first round. In that case, since there would be more than two candidates in the second round, it would be important to use
Note: this "proportional two-winner
== Relationship to NOTA ==
As discussed in the above section, if all the candidates in the first round got a majority "reject", then the voters have sent a message that none of the candidates are good, akin to a result of "[[none of the above]]" (NOTA).
== An example ==
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{{Tenn_voting_example}}
Assume voters in each city
<div class="floatright">
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!City
!Support
!Assist
!Accept
!Reject
!score
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</div>
Chattanooga and Knoxville both get under
If Memphis voters tried to strategize by rejecting Nashville
If Chattanooga and Knoxville tried to strategize by supporting each other, this has a chance of working, but Memphis could safely defend Nashville by
[[Category:Graded Bucklin systems]]
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