Ted Stern wrote:
If you aren't using IRV, then there's not a huge implementation advantage to restricting the number of ranks. So why have the restriction?What do group members think of the following primary election proposal:
- Ballots allow a voter to rank 1st, 2nd or 3rd choice candidates.
- Unlike IRV, more than one candidate can be chosen for any rank.
- Any 1st/2nd/3rd choice vote is considered an "approval" vote.
- Use Condorcet to tally.
- If a Condorcet winner exists, with more than 50% of the voters approving, then that candidate wins immediately and the seat doesn't have to be decided in the general election.
- Otherwise, eliminate candidates with less than 1% approval.
- On the general election ballot for that seat, candidates will be listed with the Condorcet winner (if any) at the top, with remaining candidates listed below in order of approval.
This would be an alternative to either Louisiana-style top two runoff or closed party primary.
I'm curious what advantages of full Condorcet might be lost by reducing the
options to only 3 ranks.
Suppose that the votes are:
499: A>C>B 492: B>C>A 9: C>A>B
Then C, a Condorcet winner with 100% approval, wins immediately.
Suppose that candidates A1, A2, and A3 entered the race, and the voters' preferences were
499: A>A1>A2>A3>C>B 492: B>C>A>A1>A2>A3 9: C>A>A1>A2>A3>B
If they voted sincerely, their ballots would be:
499: A>A1>A2 492: B>C>A 9: C>A>A1
There is now no longer a Condorcet winner. Candidate A3, with 0% approval, is eliminated, and the remaining candidates move on the general election with the ballot order A>A1>C>A2>B.
If the general election uses a Condorcet method, C still has a good chance of winning. But suppose that now B1, B2, and B3 enter the race, and the voters' preferences are:
499: A>A1>A2>A3>C>B>B1>B2>B3 492: B>B1>B2>B3>C>A>A1>A2>A3 9: C>A>A1>A2>A3>B>B1>B2>B3
The ballots now become:
499: A>A1>A2 492: B>B1>B2 9: C>A>A1
A is now a Condorcet winner with 50.8% approval, and so wins immediately.
Thus, your proposed method suffers from a perverse failure of Independence of Clones: It's possible for one candidate (A) to benefit from clones, while another candidate (B) is hurt by them, in the same election!
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