On 5/27/2013 8:52 AM, Warren D Smith wrote:
http://rangevoting.org/PuzzIgnoredInfo.html
Interesting.
Plurality and Approval collect so much less information that they do not
noticeably ignore any information.
Instant-runoff voting obviously ignores information because it only
considers preference information that "floats to the top".
Borda clearly does not ignore information, but it yields the wrong
results -- unless somehow every voter separately ranks every choice.
When I was developing VoteFair ranking -- a.k.a. the Condorcet-Kemeny
method -- I considered and then rejected the beatpath-like approach of
looking at the biggest and smallest pairwise counts. I rejected it
partly because (similar to IRV) it ignores lots of the numbers (the ones
that are not big or small). (I also rejected it because it does not
identify the second-most popular choice, the least-popular choice, etc.)
This concept of ignoring information is part of why I claim that the
Condorcet-Kemeny method is better than the Condorcet-Schulze method.
The opposite claim (that Schulze is better than Kemeny) tends to be
based on counting the number (or importance) of fairness criteria that
are met or failed. When we finally measure how often those failures
occur, the "information loss" of the Condorcet-Schulze method will
become clear. In contrast, the Condorcet-Kemeny method considers every
pairwise count, not just the biggest and/or smallest pairwise counts.
Richard Fobes
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