[EM] Compromise between IRV and Condorcet methods

[Chris Benham]

Richard,

As I just commented in my reply to Kevin,  I think Hare makes a bad a 
mixer and so is difficult to fruitfully "refine".

Can you give an example where your suggested method performs better than 
plan Hare (aka IRV)?

I think your suggested method would be quite a bit more difficult to 
hand-count than say Benham. With Benham when considering the candidate 
that Hare would next eliminate we only have to establish that it has a 
single pairwise defeat (before eliminating it), not that it loses all 
its pairwise contests.

Can you give an example where your method gives a better (or just 
different) result than Benham?

Chris


On 22/08/2025 6:47 am, Richard via Election-Methods wrote:
> On 8/21/25 11:37, Chris Benham via Election-Methods wrote:
> > *Elect whichever of the Hare winner and the most approved candidate
> > pairwise beats the other.*
>
> Here I'll put in a plug for refining IRV by eliminating pairwise 
> losing candidates when they occur.  It's a simple compromise between 
> IRV and Condorcet methods that isn't "clunky" and yields lots of "bang 
> for the buck."
>
> A pairwise losing candidate is a candidate who loses every one-on-one 
> contest against every other remaining candidate.
>
> Only when a counting round lacks a pairwise losing candidate does the 
> combined method fall back on eliminating the candidate with the fewest 
> transferred votes.
>
> Richard Fobes
>
>
> On 8/21/25 11:37, Chris Benham via Election-Methods wrote:
>> Kevin,
>>
>> Thanks for that demonstration.
>>
>> A much more simple method (using the same type of ballots) definitely 
>> does meet Mono-add-Top:
>>
>> *Elect whichever of the Hare winner and the most approved candidate 
>> pairwise beats the other.*
>>
>> James Green-Armytage mentioned a while ago that he thought that would 
>> be a good method. At the time I had different priorities and 
>> dismissed it as something clunky that fails Condorcet and Mono-raise, 
>> but now I agree. As a practical proposition it is probably doubtful 
>> that the extra complication versus plain Hare gives enough bang for 
>> buck, and I suppose as well as failing Condorcet it fails Double 
>> Defeat.  But nonetheless it must be quite a bit more Condorcet 
>> efficient than Hare, while hanging on to Mono-add-Top compliance.
>>
>> Chris
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