Majority criterion: Difference between revisions
Content added Content deleted
(→Notes) |
No edit summary |
||
| Line 5: | Line 5: | ||
The [[Condorcet criterion]] implies the majority criterion. Practically every serious ranked voting method passes the majority criterion. Most [[Cardinal voting|rated voting]] methods fail the majority criterion, such as [[Approval voting|Approval]], [[Score]], and [[STAR voting]], though this is argued to be a good thing in situations where those methods elect a candidate who is well-liked by all voters rather than a candidate who is narrowly preferred by a majority but loathed by the minority. |
The [[Condorcet criterion]] implies the majority criterion. Practically every serious ranked voting method passes the majority criterion. Most [[Cardinal voting|rated voting]] methods fail the majority criterion, such as [[Approval voting|Approval]], [[Score]], and [[STAR voting]], though this is argued to be a good thing in situations where those methods elect a candidate who is well-liked by all voters rather than a candidate who is narrowly preferred by a majority but loathed by the minority. |
||
Example: |
Example:<blockquote>51 A |
||
51 A |
|||
25 B>C |
25 B>C |
||
| ⚫ | |||
24 C>B |
|||
| ⚫ | |||
| Line 23: | Line 19: | ||
with the likely most general interpretation of "vote ahead of" being "ranked or rated higher than". |
with the likely most general interpretation of "vote ahead of" being "ranked or rated higher than". |
||
=== The majority criterion for rated ballots === |
|||
The majority criterion for rated ballots is a weaker, separate criterion which says that a candidate given a perfect (maximal) rating by a majority of voters must win if no other candidate received a perfect rating from that majority. |
The majority criterion for rated ballots is a weaker, separate criterion which says that a candidate given a perfect (maximal) rating by a majority of voters must win if no other candidate received a perfect rating from that majority. |
||
The difference between the two versions can be seen with this example: |
The difference between the two versions can be seen with this example: <blockquote>51 A:1 |
||
51 A:1 |
|||
49 B:5 |
|||
If the highest score is a 5, then the majority criterion for rated ballots allows either A or B to win. This is in contrast to the regular majority criterion, which requires A to win. Arguably, the majority criterion for rated ballots is more appropriate in the context of rated ballots, since a voter who doesn't give their 1st choice a perfect score is essentially choosing not to use all of their voting power, and thus their preference need not be (or even perhaps, shouldn't) be maximally respected or enforced. |
49 B:5 </blockquote>If the highest score is a 5, then the majority criterion for rated ballots allows either A or B to win. This is in contrast to the regular majority criterion, which requires A to win. Arguably, the majority criterion for rated ballots is more appropriate in the context of rated ballots, since a voter who doesn't give their 1st choice a perfect score is essentially choosing not to use all of their voting power, and thus their preference need not be (or even perhaps, shouldn't) be maximally respected or enforced. |
||
== Notes == |
== Notes == |
||