ICA/ICT/SICT - So what about "improved Condorcet" methods?
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I recently read more about the class of "improved" Condorcet methods. Which use the tied at the top rule to redefine the notion of a Condorcet winner. It is claimed that this fixes favorite betrayal and possibly the chicken dilemma, while also being close to Condorcet methods.
This seems promising, so I wonder why there isn't much talk about them. Even from a practial viewpoint they are easier to explain than for example Schulze, or Smith//score.In particular I am talking about Improved Condorcet Approval and Symmetrical Improved-Condorcet-Top.
The first article also describes a variant:
The above definition defines t[a,b] to be the number of voters tying a and b in the top position. ... However, it might be more intuitive, and preferred, if t[a,b] were defined rather as the number of voters ranking a equal to b and explicitly voting for both.
Why would that be preferred? And does this only work when explicitly ranking/approving both, or also for bottom ranks? In that case one could state the rule as just: "A candidate is unbeaten if there is no other candidate that is ranked higher by more than half of all voters." Which also would be easier to calculate and visualize.
Is there any reason not to extend ICA to ICscore using a rated ballot? ICscore could then be easily explained as "Rate all candidates on a scale from 0 to 5. Remove all candidates where some other candidate is preferred by more than half of voters. Of the remaining, elect the one with highest score."
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@Casimir said in ICA/ICT/SICT - So what about "improved Condorcet" methods?:
Why would that be preferred? And does this only work when explicitly ranking/approving both, or also for bottom ranks? In that case one could state the rule as just: "A candidate is unbeaten if there is no other candidate that is ranked higher by more than half of all voters." Which also would be easier to calculate and visualize.
If ties count in favor of both candidates when they are compared, then at the bottom ranks, voters would want to make up a ranking for those candidates just because it would hurt whoever is put lower in the ranking.
Generally, this system reminds me of a system I thought about a while ago but I don't know if I wrote about it anywhere. (The thinking behind them is basically the same.) It works like Minimax Condorcet with co-equal ranks, but there is an approval-like cutoff in the ranking. For tied candidates above a ballot's cutoff, the ballot counts for both candidates in that pairwise matchup. For tied candidates below a ballot's cutoff, the ballot counts against both candidates in that pairwise matchup.
Ultimately the thing that I really don't like about that system is that the notion of a coequal ranking is deceptive: coequal rankings sound like they are intended to indicate that you support both candidates equally, but the system is designed so that they really serve a strategic purpose.
