Truncated ballots

[Saari]

In a message dated 98-04-06 15:13:13 EDT, you write:

<<    Example:
    35%:  ABC
    16%:  BAC
    16%:  BCA
    33%:  CBA
 
    I presume we're all agreed that B should be elected here 
    given these voter preferences. >>

Sorry, there is not enough information available to make this conclusion.  It
is possible that the first three groups find ALL of the candidates
"acceptable", whereas the last group finds C "acceptable" but is violently
opposed to B and A.  If this were the true situation, we could summarize by
saying that only candidate C is acceptable to the entire group.

In another situation (with the same appearance of these simple rankings) it
might turn out that A was the only candidate acceptable to the whole group.
Or perhaps B.  

In general, simple ranking does not convey enough information to make clear
conclusions - but it does provide just enough data for people to argue
endlessly without possibility of success.

Mike Saari