[EM] IRV fails Later-No-Harm

MIKE OSSIPOFF nkklrp at hotmail.com
Tue Dec 23 17:53:02 PST 2003

Chris Benham wrote:

"Later-no-harm:  Adding a later preference to a ballot should not harm
any candidate already listed".

In other words, if  a method meets Later-no-harm then  voters can never
get an advantage by truncating.
It is met by IRV, but is incompatible with  Condorcet.
I got this from what I found to be the very interesting and illuminating
paper "Monotonicity and Single-Seat Election
Rules" by Woodall, and uploaded by  Marcus Schulze:

I reply:

Professor Steven Brams published an example in which IRV fails 
No-Later-Harm. I'd post the example, but I don't know where to look for it. 
You could find it just as well as I could.

Mike Ossipoff

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