Re: [EM] Condorcet IRV Hybrid
On Fri, Apr 5, 2013 at 2:43 PM, Kristofer Munsterhjelm wrote:
> On 04/05/2013 09:37 PM, Forest Simmons wrote:
>
> The following observation about Condorcet IRV Hybrids has probably
>> already been made (but I have been gone for a while):
>>
>> These hybrids have no good defense against burying. For example
>>
>> Sincere ballots:
>>
>> 40 A>C
>> 35 B>C
>> 25 C>A
>>
>> If the A faction decides to bury C, there is nothing the C faction can
>> do about it unilaterally. They have to depend on the willingness of the
>> B faction to elevate their compromise over favorite.
>>
>
> That's strange, because one of the points of James Green-Armytage in his
> voting strategy paper was that the Condorcet-IRV hybrids were significantly
> less prone to burying than ordinary Condorcet methods. Quoting,
>
> "All Condorcet-efficient methods are vulnerable to burying, but this
> vulnerability seems to be substantially less frequent in the Condorcet-Hare
> hybrids than in most other Condorcet methods. The reason for this is that
> voters who prefer q to w will already have ranked q ahead of w, so that
> further burying w will not affect w's plurality score unless q has already
> been eliminated."
>
> ("Four Condorcet-Hare Hybrid Methods for Single-Winner Elections",
> http://www.econ.ucsb.edu/~**armytage/hybrids.pdf,
> p. 8)
>
> Or are we talking about different things? Perhaps C/IRV methods are less
> vulnerable to burying in the first place, but when they are, it's harder to
> employ defensive strategy to correct the burial?
>
> -
>
> Also, I seem to recall that Uncovered,X is generally more susceptible to
> burial than is X for various types of X, unless X is already rather
> susceptible to burial. It might be interesting to run a JGA type analysis
> on your "eliminate until covering" method, and compare to the Smith-IRV
> methods.
>
> The method I proposed is not of the type "Uncovered X." The first
candidate to cover the remaining candidates may well be a covered candidate
herself.
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Re: [EM] Sequential STV method (Oops)
On 04/07/2013 10:19 AM, Kristofer Munsterhjelm wrote: On 04/07/2013 03:59 AM, Ross Hyman wrote: More general variant: Candidate sets of N candidates are notated by Greek letters. [snip] You said that this method was based on a cloneproof single-winner method. Sorry about the 3x duplication. My mail server glitched. If any moderators see this, just remove the other duplicates :-) Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Sequential STV method
On 04/07/2013 03:59 AM, Ross Hyman wrote: More general variant: Candidate sets of N candidates are notated by Greek letters. [snip] You said that this method was based on a cloneproof single-winner method. Woodall generalized the clone criteria in http://www.votingmatters.org.uk/issue3/p5.htm to "Clone-in", "Clone-no-harm", and "Clone-no-help", so clone independence could more easily be applied to multiwinner methods. He noted that "Clone-no-harm" conflicts with the DPC, and generally, isn't desirable in proportional multiwinner methods. My question is then: do you know whether the multiwinner method you've given passes the clone independence criteria useful for multiwinner methods (i.e. "clone-in" and "clone-no-help")? Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Sequential STV method
On 04/07/2013 03:59 AM, Ross Hyman wrote: More general variant: Candidate sets of N candidates are notated by Greek letters. [snip] You said that this method was based on a cloneproof single-winner method. Woodall generalized the clone criteria in http://www.votingmatters.org.uk/issue3/p5.htm to "Clone-in", "Clone-no-harm", and "Clone-no-help", so clone independence could more easily be applied to multiwinner methods. He noted that "Clone-no-harm" conflicts with the DPC, and generally, isn't desirable in proportional multiwinner methods. My question is then: do you know whether the multiwinner method you've given passes the clone independence criteria useful for multiwinner methods (i.e. "clone-in" and "clone-no-help")? Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Sequential STV method
On 04/07/2013 03:59 AM, Ross Hyman wrote: More general variant: Candidate sets of N candidates are notated by Greek letters. [snip] You said that this method was based on a cloneproof single-winner method. Woodall generalized the clone criteria in http://www.votingmatters.org.uk/issue3/p5.htm to "Clone-in", "Clone-no-harm", and "Clone-no-help", so clone independence could more easily be applied to multiwinner methods. He noted that "Clone-no-harm" conflicts with the DPC, and generally, isn't desirable in proportional multiwinner methods. My question is then: do you know whether the multiwinner method you've given passes the clone independence criteria useful for multiwinner methods (i.e. "clone-in" and "clone-no-help")? Election-Methods mailing list - see http://electorama.com/em for list info
