[EM] Can someone point me at an example of the nonmonotonicity of IRV?

[Juho]

On Aug 10, 2008, at 7:13 , Kathy Dopp wrote:

>> All election methods have vulnerabilities. These monotonicity
>> failures may look bad on paper but in real life elections they are
>> typically not that harmful. If some IRV voter asks if he should vote
>> sincerely or falsify his vote somehow due to the non-monotonic
>> properties the general recommendation is anyway to vote sincerely. It
>> is not easy to use the monotonicity failures to intentionally  
>> improve/
>> falsify the results (in typical large public elections).
>
> "not easy"?! I'd say it is impossible since most voters I know do not
> read minds of all the other voters or know how all the other voters
> voted prior to casting a ballot. However, I suppose if one were an
> insider who is manipulating the election results after the election,
> it would be possible - so OK, it is possible.
>
>
> Hey, maybe I'm just wierd or something, but I prefer knowing whether
> or not I should rank a candidate first, middle or last to help that
> candidate win when I go to the polls.

If in doubt I'd recommend also in IRV to rank the first ones first.  
It is much more probable that doing so will contribute positively to  
the end result rather than contribute negatively.

>
> Are you *sure* I haven't fallen down the rabbit hole?

In the world of election methods there are indeed many strange rabbit  
holes. One must just check them all to see which ones are just  
harmless paradoxes, which ones are nasty but with no crucial impact,  
and which ones make the methods unusable.

Juho


>
> Cheers,
>
> Kathy
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