Reciprocal Score Voting: Difference between revisions

[[Score voting]] and other cardinal systems are susceptible to the [[chicken dilemma]] and other situations which occurs when similar groups penalize one another by not cooperating. '''Reciprocal Score Voting''' is an unusual attempt to address this lack of cooperation by explicitly and safely rewarding it.

 

The idea is to tie how much support a faction's preferred candidate receives from other factions by how much that candidate's faction has supported those other factions. In other words, support must be given to be received, encouraging reciprocation. Hence the name.

 

[[File:Reciprocal Score Voting Yee diagrams.png|thumb|400px|right|[[Yee diagram|Yee diagrams]] for Reciprocal Score Voting, showing non-monotonicity and small amounts of [[center squeeze]].]]

 

Each ballot is assigned to one or more factions, based on the top rated candidates in that ballot. Then the ballots of each faction are used to run mini score voting elections, the results of which represent how well each faction rates every other faction.

 

Only when factions agree on their mutual ratings and perfectly reciprocate is that their ''reciprocity ratio'' <math>F_{j \to \phi} / F_{\phi \to j} = 1</math>, in which case votes are left unchanged.

 

In the case of any asymmetry in support, the reciprocity ratio is <math>F_{j \to \phi} / F_{\phi \to j} < 0</math> for the faction which did not cooperate, and <math>F_{j \to \phi} / F_{\phi \to j} = 1</math> for the faction that did cooperate. Therefore, not cooperating penalizes the side which did not cooperate more. In this way, factions are encouraged to cooperate as much as possible to maximize mutual support, forcing them to strike a balance between supporting their favorite as well as supporting alternatives as much as they can. In the case of opposing factions, the mutual lack of cooperation has no effect.