[EM] Strategy-proof vs Monotone

[Richard Lung]

km,

Well you've quoted from my explanation, some of it. My keep value 
"book-keeping" is unique to binomial stv, so you can't use traditional 
stv as a standard of comparison, which you seem to be doing.

Meek method employs keep values for elected candidates, but not for all 
candidates, allowing a universal standard of comparison, and not for an 
exclusion count, as well as an election count.

I fully agree with you that computational tests have their thoro part to 
play. I think they would be useful for a previous consideration you 
raised. Personally, I don't think they would unearth the present 
problems, being considered. I regret if my three cited e-books are not 
what you require.


Regards,

Richard Lung.



On 19/01/2022 21:38, Kristofer Munsterhjelm wrote:
> On 19.01.2022 22:16, Richard Lung wrote:
>> km,
>> You are repeating what the rest of my post already says -- the need
>> for testing in realistic scenarios. -- Not so much to test monotonicity
>> and strategy resistance. That is guaranteed by the removal of the ad hoc
>> premature exclusion of candidates. And replacing it with an exclusion
>> count, symmetrical to, or exactly the same as the election count,  That
>> is a transferable vote, known to be monotonic -- and hence so, in an
>> exclusion count as well as an election count.
> You are saying that a particular procedural mechanism ensures
> monotonicity and strategy resistance. I doubt that this can be inferred
> simply from procedural design, because it's very easy to come up with
> something that seems right but turns out to have a subtle weak spot.
>
> I would like to have an implementation so that I could at least see
> whether a computer search could find any monotonicity failures, and so
> that the strategy resistance could be indicated in a similar way to what
> Daniel is doing.
>
> That's what I'm saying. Of course surprise is not an argument; I am
> simply saying that, in the absence of anything more conclusive and
> readily available, my experience is all I've got, and that experience
> indicates that monotonicity in STV is very difficult, and that monotone
> strategy resistance is even more difficult.
>
> That is not a proof that your method isn't monotone, but I didn't claim
> that it constituted such a proof. Just that when you keep saying that
> your STV method (unlike other STV methods) is provably monotone, I would
> like to see the goods for myself, as it were.
>
> -km