AV/IRO with equal rankings

Mike Ositoff ntk at netcom.com
Thu Nov 12 20:10:20 PST 1998

> There was some discussion a while back about how to handle equal
> rankings in IRO.  The two methods discussed were fractional votes, and

Here's how:

"Repeatedly eliminate from the rankings the candidate who
occupies or shares highest position in fewest rankings."

By allowing equal rankings, counting by the above rule, 
the voter can choose between voting as in Approval or IRO,
or both. It would be an ideal compromise between advocates
of Approval & of IRO.

> treating them as multiple whole votes.  I believe it was decided that it
> wouldn't make sense for anyone to use fractional votes, while allowing
> multiple votes would cause a rich party problem (and also violate the
> spirit of IRO).

If you were to re-word the above rule in terms of "votes", so
that voters had more than 1 vote, that doesn't cause a rich
party problem. The rich party problem is  a specifically defined
problem shared by Copeland, Dodgson,  & maybe a few other

> It seems to me that the only remaining solution would be to use these
> votes conditionally, in effect creating a ranking for them at the time
> they are actually used.  You could do this based on the strength of the

Understand that you're defining an entirely new method,
and can't really call it a version of IRO anymore.

> candidates in question, so that a vote for (A=B) would be interpreted as
> A > B if A had more unconditional votes.  Note that the opposite

With my proposed Approval IRO rule, ranking A & B equally as
1st choices will have no effect on whether A eliminates B or
vice versa, in the 1st round. There's no need to have a special
rule to count votes conditionally.


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