Distributed Score Voting: Difference between revisions
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Graphically, each candidate is a node; the head-to-head is represented by an arrow, leaving the winning candidate, entering the losing candidate. The tie is represented as a double arrow entering, that is both candidates are considered losers.
2) Find the smallest set X (Smith set) of nodes that don’t have incoming arrows, coming from outside the set.
Then remove all candidates not in X from the votes.
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6) If you want to know the % of victory of the winning candidates then, in each original vote, you must remove all the candidates who haven’t won, and normalize* the vote with the formula used in point 3 (with W=100 fixed). The sum of points for each candidate will indicate the % of victory.
===Head-to-head===
In a head-to-head between candidates A and B, a vote like A[10], B[30], C[60], D[0] could be treated in 2 different forms:
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To make the writing of the vote more comprehensible and simple, the voter can be left with almost complete freedom in the use of numerical values or only X.
Before the counting process, the
Examples of how a vote can be written by the voter and subsequently, in the counting, converted into 100 points:
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The complexity in writing the vote adapts to the voter, and it’s also noted that, if 101 or 99 points are mistakenly distributed, the vote will still be valid.
==Criteria==
Criteria met by DSV:
* Majority criterion
* Majority loser criterion
* Mutual majority criterion
* Condorcet criterion
* Condorcet loser criterion
* Smith criterion
* Independence of irrelevant alternatives
* Independence of clones criterion
* Monotonicity criterion
* Reversal symmetry
* Pareto criterion
Criteria not met by DSV:
* Participation criterion
* Consistency criterion
* Later-no-harm criterion
* Later-no-help criterion
* Favorite betrayal criterion
The first two criteria not met are derived mainly from the fact that DSV wants to ensure the victory of the candidate who wins all the head-to-head (when it exists).
The last 3 unmet criteria can instead generate tactical votes, described below.
===Tactical votes===
In an election, the results of the head-to-head are the following: A>B , B>C , C>D , D>A , A>C , D>B and in the end wins B.
A voter who in this case supported the candidates as follows: A>D>B>C he could change his vote as follows: A>D>C>B to favor C more than B (without disadvantaging A and D).
This tactical vote could cause B to lose head-to-head between B and C and in this case B would be the candidate who loses all head-to-head, being eliminated immediately. The winner would no longer be B.
This type of tactical vote works only if:
* there is a condorcet paradox which includes at least 4 candidates.
* through the tactical vote, the candidate who should have been the winner can be taken out of the Smith set.
* the new winner is actually a better candidate than the previous one (the new winner in the example could also be C).
* the voter has a fairly precise knowledge of the likely ballots result, without which this tactical vote would turn against him.
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