River: Difference between revisions
Content added Content deleted
No edit summary |
imported>Araucaria (Added summary of method) |
||
Line 1: | Line 1: | ||
River is a cloneproof monotonic [[Condorcet_method#Different_ambiguity_resolution_methods|Condorcet ambiguity resolution method]] with similarities to both [[Ranked Pairs]] and [[Cloneproof Schwartz Sequential Dropping]], but when cycles exist, can in rare cases find a different winner than either of the other two methods. |
River is a cloneproof monotonic [[Condorcet_method#Different_ambiguity_resolution_methods|Condorcet ambiguity resolution method]] with similarities to both [[Ranked Pairs]] and [[Cloneproof Schwartz Sequential Dropping]], but when cycles exist, can in rare cases find a different winner than either of the other two methods. |
||
Quick summary of method, which is identical to Ranked Pairs except where emphasized: |
|||
* Rank defeats in descending order of winning vote strength. |
|||
* Starting with the strongest defeat, affirm defeats unless a cycle is created ''or a candidate is defeated twice''. |
|||
The result is that only sufficient defeat information to determine the winner is included. |
|||
Because not all defeats are processed, the social ordering is not linear -- in general it is a tree (or river) diagram, with the victor at the base of the river. |
|||
It was first proposed by [[User:Heitzig-j|Jobst Heitzig]] on the [[Election-methods mailing list]]: |
It was first proposed by [[User:Heitzig-j|Jobst Heitzig]] on the [[Election-methods mailing list]]: |
||
Line 7: | Line 15: | ||
* [http://lists.electorama.com/pipermail/election-methods-electorama.com/2004-October/014102.html Example using 2004 baseball scores]. This shows how a 14-candidate election winner can be determined much more quickly using River than with RP or Beatpath. |
* [http://lists.electorama.com/pipermail/election-methods-electorama.com/2004-October/014102.html Example using 2004 baseball scores]. This shows how a 14-candidate election winner can be determined much more quickly using River than with RP or Beatpath. |
||
* [http://lists.electorama.com/pipermail/election-methods-electorama.com/2004-April/012678.html Early criticism of the River method]. This shows that the River method violates mono-add-top and mono-remove-bottom |
* [http://lists.electorama.com/pipermail/election-methods-electorama.com/2004-April/012678.html Early criticism of the River method]. This shows that the River method violates mono-add-top and mono-remove-bottom |
||
<!-- |
|||
(Emacs settings) |
|||
Local variables: |
|||
fill-column: 1024 |
|||
End: |
|||
--> |