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Technical discussion of election methods

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IRV vs Coombs

FS
Forest Simmons
Thu, Mar 30, 2023 5:44 PM

Coombs suffers from Burial vulnerability, while IRV suffers from
Compromising.

Here's a hybrid version that is much better than either by itself:

  1. Check for an undefeated candidate among those remaining ... (and
    announce the victory party if there is one).

  2. Find the pairwise loser (PL), between the remaining candidate with the
    smallest Top count and the one with the largest bottom count.

  3. Eliminate this PL along with every candidate that does not defeat it
    pairwise.

  4. If more than one candidate remains, repe

at these steps.

If, in step 2, the Min Top and Max Bottom are the same, then use it as the
PL.

This easy to use, and perhaps the best Burial resistant method so far.

a A>B
b B>C
c C>A

Assuming a>b>c so C is both min Top and Max Bottom.

Eliminate C and the candidate it beats (A) .... leaving B as the winner.

48 C
28 A>B
24 B

The smallest Too count is B's ... biggest Bottom count is A's ... the PL is
B. B takes down C with it, leaving A.

Check A's defeat over C with fresh, one purpose (therefore sincere) ballots
if desired.

-Forest

Coombs suffers from Burial vulnerability, while IRV suffers from Compromising. Here's a hybrid version that is much better than either by itself: 1. Check for an undefeated candidate among those remaining ... (and announce the victory party if there is one). 2. Find the pairwise loser (PL), between the remaining candidate with the smallest Top count and the one with the largest bottom count. 3. Eliminate this PL along with every candidate that does not defeat it pairwise. 4. If more than one candidate remains, repe at these steps. If, in step 2, the Min Top and Max Bottom are the same, then use it as the PL. This easy to use, and perhaps the best Burial resistant method so far. a A>B b B>C c C>A Assuming a>b>c so C is both min Top and Max Bottom. Eliminate C and the candidate it beats (A) .... leaving B as the winner. 48 C 28 A>B 24 B The smallest Too count is B's ... biggest Bottom count is A's ... the PL is B. B takes down C with it, leaving A. Check A's defeat over C with fresh, one purpose (therefore sincere) ballots if desired. -Forest