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

[Kathy Dopp]

> From: "rob brown" <rob at karmatics.com>
> Subject: Re: [EM] Can someone point me at an example of the
>        nonmonotonicity of IRV?

> Are you aware that in going to a doctor to treat an injury, you can get in a
> car accident and get injured some more?  Why would anyone go to a doctor if
> doing so can actually make your health WORSE?

OK. So you are saying we must use voting methods where voting for our
FIRST-Choice candidate as our LAST Choice helps our first choice
candidate win, and when I go to the polls I have no idea if that is
true or false because "I might get into an accident when I drive to
the doctor when I'm sick?

I must have fallen down the rabbit hole when I joined this list.


>
> Just because there is a non-zero chance of harm resulting from your choice
> does not mean that you should be paralyzed from making a decision.

I am *not* paralyzed. I have DECIDED that I IRV voting is an insane
voting method that would cause much more havoc with voting systems.

> I also think you are putting far too much emphasis on people's first choice
> candidate, as if all results other than the first choice candidate winning
> are equally bad.  This way of thinking seems to be a common symptom of being
> accustomed to plurality and the two party system that results from it.  In
> an election with many candidates, if you hurt your first choice candidate's
> chances, but you help your second choice beat your least favorite, is that
> really so bad?

Nope. Never said it was and I have no problem with voting methods that
do such things, but you may have neglected to notice that with IRV,
ranking my first-choice LAST could help my first-choice MORE than
ranking my first-choice FIRST. In IRV, putting my candidate FIRST can
help my LAST place candidate win and putting my candidate LAST can
help my FIRST place candidate win.

Please identify all the other voting methods for me which have that
property (that ranking or rating a candidate LAST can help that
candidate MORE than ranking or rating a candidate FIRST) in addition
to IRV so that I can oppose them as well because I am not familiar
with any of these other methods that share that property with IRV.

Thank you in advance.

Really I must have fallen down the rabbit hole.


> From: Juho <juho4880 at yahoo.co.uk>
> Subject: Re: [EM] Can someone point me at an example of the
>        nonmonotonicity of IRV?

>
> 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.

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

Cheers,

Kathy