Rated pairwise preference ballot: Difference between revisions
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The second type of transitivity is based on [[Score voting]] and the idea that a voter's preferences should fit in a scale. Note however that with rated pairwise, a cap must be artificially imposed such that a voter's preference can't exceed 100%; this cap is not needed in Score, because in order for the voter to indicate a 100% marginal preference in any pairwise matchup, they must put their preferred candidate at the max score, and their less-preferred candidate at the min score; this inherently prevents them from further increasing their marginal preference by shifting either candidate up or down in terms of score.
This form of ballot may be cast by first requesting a full ranking, followed by pairwise margins between neighboring candidates. Margins of 0 would indicate equal rankings. Visually, this can be presented as a cardinal evaluation for the ">" operation itself:
[0.5] [0.3] [0.0] [1.0]
A > B > C = D > E
We then see that A > C,D must be at least 80% of a margin.
Both of these transitivity requirements are automatically fulfilled in standard Condorcet using ranked ballots, because if the voter indicates any preference for A>B and B>C, then this will count as 1 vote (100% support) for A>B and B>C each, and because ranked transitivity ensures that this voter must indicate an A>C preference, that will also be counted as a 100% strong preference.
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