[EM] renaming DYN

2007-07-23 Thread Forest W Simmons
Googling DYN shows that these initials are already spoken for (though not in the context of voting). The initials PXSV are not spoken for, so unless someone comes up with a better set of letters, I would like to use these letters for "PSX Voting". These letters have the advantage of being very

Re: [EM] "Social Utility Will Look After Itself"

2007-07-23 Thread Forest W Simmons
Chris B wrote... > >Regarding "social utility", I'm of the school that says that to the >extent that it is a real and wonderful thing it will look after itself >if we do >our best to ensure that the election method is as fair and >strategy-resistant as possible. Random Ballot is already fair a

Re: [EM] Intermediate Ratings Never Optimal?

2007-07-22 Thread Forest W Simmons
One of the basic theorems of Linear Programming is that when there is an optimal value of a linear objective function it will occur at least one corner of the feasible region. In the rare cases that it occurs at two corners of the feasible region, it will also occur at every point on the line

Re: [EM] Some Approval strategies

2007-07-21 Thread Forest W Simmons
Mike, Thanks for reminding us of the basic approval strategies that are easy to apply. Still there are those who would rather have a strategy free method without having to rank all of the candidates, while still being able to give their favorite candidate special support above mere approval.

Re: [EM] When Voters Strategize, Approval Voting Elects Condorcet

2007-07-17 Thread Forest W Simmons
Mr. Schudy's article reinforces the rationale behind DYN: that with reliable partial information, Approval does as well or better than Condorcet. Mr. Schudy treats the case in which there is a clear frontrunner and a clear runnerup. In that case he shows that (what we usually call) "approval

Re: [EM] DYN

2007-07-12 Thread Forest W Simmons
In further response to Juho's question about candidates making their approval choices before versus after the partial count, here's a compromise: Require the candidates to publish their candidate rankings before the election, and then (after the partial info is available to them) require them

Re: [EM] DYN

2007-07-12 Thread Forest W Simmons
True, it would be confusing to explain DYN as a form of asset voting, but it could be done. Here is its purest form: Each voter gets one vote per candidate. The voter delegates each vote to a candidate (the one that she wants to make responsible for getting a Y or N attached to that vote).

Re: [EM] election-methods Digest, Vol 37, Issue 8

2007-07-12 Thread Forest W Simmons
In response to Juho's questions: There are various possible versions of DYN. But if the candidates were required to give their approvals before learning the partial results, then there would be little point in delegating votes; the voters could just copy the candidate recommendations onto thei

[EM] DYN

2007-07-09 Thread Forest W Simmons
Delegable Yes/No: Each voter has a Yes/No vote to cast for each candidate. The voters can delegate some of these votes to candidates (including write-ins), if they so desire. The candidates cast the delegated votes after the rest of the votes have already been counted. Thus the voters that h

[EM] DSV

2007-07-05 Thread Forest W Simmons
Raphfrk had a question about Declared Strategy Voting. Yes, originally DSV was limited to Batch and vote-by-vote versions of plurality strategies applied to ordinal ballots. But on this election methods listserv we have expanded DSV to include any method that takes rankings or ratings and autom

Re: [EM] election-methods Digest, Vol 37, Issue 5

2007-07-05 Thread Forest W Simmons
;From: [EMAIL PROTECTED] >Subject: Re: [EM] election-methods Digest, Vol 37, Issue 4 >To: election-methods@electorama.com >Message-ID:

Re: [EM] feedback loops in elections and election methods

2007-07-03 Thread Forest W Simmons
Designated Strategy Voting (DSV) methods relieve the voter of repeated returns to the polls for each iteration of the feedback loop, and also solve the anonimity requirement, but as has been noted, methods that are supposed to iterate unto an equilibrium may not converge. [What follows requires

Re: [EM] manipulation free method?

2007-07-03 Thread Forest W Simmons
Mike, Yes, the approval strategist would do well with this method. Those who like to strategize can do so, and those who don't like to can just rank the candidates. Those who don't strategize will (by definition) submit sincere rankings. Those who do strategize can do most, if not all, of th

Re: [EM] Manipulation Free?

2007-06-30 Thread Forest W Simmons
It appears that the answer to the question is no, but not too bad. Taking into account suggestions by Warren, Mike, and Dave, I offer a simpler version. The basic ballot is ordinal. Everything else is optional. Voters with opinions about who has the best chance of winning can put a mark next t

Re: [EM] manipulation free method?

2007-06-29 Thread Forest W Simmons
It's true that there can be some incentive to lie about whom you think is the most likely to win, but there is no point in lying about your preference order. Here's a version that reduces the incentive to lie about perceived probabilities: Each person indicates both a guess as to the winner, a

[EM] manipulation free method?

2007-06-28 Thread Forest W Simmons
I was happy to see Alex Small's progress on the FBC. It inspired me to take another crack at some way of getting around the basic impossibility of manipulation free deterministic methods based on standard ranked ballots. Obviously, to surmount this basic obstacle we need other information from

[EM] Approval Equilibrium

2007-06-13 Thread Forest W Simmons
Suppose that candidate Y has the greatest pairwise opposition against candidate X. Let the letter n represent the number of ballots on which Y is rated strictly above X, i.e. X's maximum pairwise opposition. If X is an approval equilibrium winner, then the equilibrium approval of Y will be at

[EM] Approval Equilibrium

2007-06-12 Thread Forest W Simmons
What is an approval equilibrium? Is it possible to deduce an approval equilibrium from sincere rankings or ratings? These questions are amazingly slippery! I won't attempt to survey the many answers that have been proposed, but I would like to share a line of thought that came to me after pond

[EM] Conditional Approval (was "Does this method have a name?")

2007-05-16 Thread Forest W Simmons
idates, and go with the winner of the cycle that maximizes the min conditional approval of its cycle winner. Forest >From: Forest W Simmons <[EMAIL PROTECTED]> >Subject: Re: [EM] Does this method have a name? > > >The "reactive approval" of candidate X relative to

Re: [EM] Does this method have a name?

2007-05-14 Thread Forest W Simmons
The "reactive approval" of candidate X relative to Y as defined below is supposed to approximate the approval that X would get given only that Y was ahead of all the other candidates in the polls. In other words, if there were zero info up until someone reveals that Y is the front runner, would

Re: [EM] Does this method already have a name?

2007-05-12 Thread Forest W Simmons
Here's an example that might clear up some questions: Suppose that the original ballot is A=B>C=D>E=F|G=H>I=J>K=L where "|" is the voter's marked approval cutoff. Then in calculating reactive approvals relative to C we move the approval cutoff adjacent to but not past the position shared by C

Re: [EM] Does this method already have a name?

2007-05-09 Thread Forest W Simmons
's score is her minimum reactionary approval relative to the other candidates. " then we get another method not equivalent to MinMax in the complete ranking case. Forest >From: Forest W Simmons <[EMAIL PROTECTED]> >Subject: [EM] Does this method already have a name? >To:

[EM] Does this method already have a name?

2007-05-07 Thread Forest W Simmons
Ballots are ordinal with approval cutoffs. The candidate with "Maximum Minimal Reactionary Approval" wins. A candidate's "reactionary approval" relative to another candidate is the approval she would get if the approval cutoff were moved adjacent to (but not past) the other candidate's position

Re: [EM] utility functions for Yee diagrams

2007-04-26 Thread Forest W Simmons
Warren, I think I understand the source of our difference in thinking. I haven't been taking "issue space" literally enough. Or from another point of view, I haven't been thinking of the voters' ratings as a function of position in issue space, but only as a function of their distances from th

Re: [EM] Approval-Sorted Margins(Ranking) Elimination

2007-04-16 Thread Forest W Simmons
I would like to see how the Yee/BOlsen diagrams for this method compare with those of IRNR (Instant Runoff by Normalized Ratings), for example. Chris Benham wrote: >Hello, >My current favourite plain ranked-ballot method is "Approval-Sorted >Margins(Ranking) Elimination": > >1. Voters ra

[EM] Summability (Efficient Parallelizability)

2007-04-06 Thread Forest W Simmons
For practical purposes any method based on rankings or range style ballots, can be closely approximated by a summable version. Since approval cutoffs can be incorporated into rankings and ratings, methods that require approval cutoffs can also be efficiently accomodated. It's based on the idea

Re: [EM] final support

2007-04-03 Thread Forest W Simmons
Approval Margins should have been on my list of most promising, even though it is not as well known as the three that I mentioned. Total Approval would not be that well known except that DMC has received a lot of attention, and DMC is equivalent to River(TA), etc. which, admittedly, may not be

[EM] final support

2007-03-30 Thread Forest W Simmons
So far, the three most promising measures of defeat strength for Beatpath and the other immune methods are ... 1. Winning Votes: the number of ballots in favor of the pairwise win. 2. Total Approval: the number of ballots on which the pairwise winner is approved. The Beatpath, Ranked Pairs, an

[EM] PG-MPO

2007-03-28 Thread Forest W Simmons
This method was introduced in the middle of another thread, but not as well as it deserved, so here goes again: Ballots are range style. Let R be the highest range value such that if all of the alternatives that are rated at or above level R are advanced to Equal Top, then for some alternative

Re: [EM] EQTOP-MPO MAMPO example

2007-03-27 Thread Forest W Simmons
I never claimed that EQTOP-MPO satisfied any strategy free criteria. To the contrary I pointed out the drawback that it requires approval style strategy even in the zero info case. That method was just the introduction to a better method that immediately followed it in the same message. Here'

[EM] MAMPO variations

2007-03-24 Thread Forest W Simmons
Thanks, Kevin, I should have known that Woodall would have already considered this in his systematic way. BTW, the more I think about MAMPO, the more I like it. How about three slot MAMPO? How about this variation of Chris Benham's idea?: For each candidate X, let EQF(X) be the number of ballo

Re: [EM] Greatest Majority Consent

2007-03-22 Thread Forest W Simmons
email, send a message with subject or body 'help' to > [EMAIL PROTECTED] > >You can reach the person managing the list at > [EMAIL PROTECTED] > >When replying, please edit your Subject line so it is more specific >than "Re: Contents of election-method

[EM] Greatest Majority Consent (GMC)

2007-03-22 Thread Forest W Simmons
This method has the same relationship to Beatpath that MMPO has to MinMax. Let's call the opposite of opposition, consent. Then MMPO which is an abbreviation for Min Max (pairwise opposition) could be characterized as Max Min (pairwise consent). To be definite, the pairwise consent for A rela

Re: [EM] Directional Resistance

2007-03-22 Thread Forest W Simmons
Michael Poole worried that it might be impossible to find circuit elements with the precise properties needed. As always, theoretical circuits have elements with idealized properties. An idealized diode of the kind we need with reisitance R1 in one direction and R2 in the other direction coul

[EM] Directional Resistance

2007-03-21 Thread Forest W Simmons
Has anybody explored this idea? Make an electrical circuit with a terminal for each candidate. For each pair of terminals attach a diode that has a different resistance in each direction: the resistance in the direction from candidate i to candidate j is proportional to the number of ballots

[EM] another example of using virtual candidates

2007-03-19 Thread Forest W Simmons
Ballots are range with finite number of range choices. Think of the cutoff between each range value as a virtual candidate. List all of the candidates, virtual or not, in order of median range value. While any candidate pairwise beats its immediate superior, swap the highest such pair in the l

[EM] A natural variation on DMC

2007-03-19 Thread Forest W Simmons
If we include the approval cutoff "App" as a virtual candidate in DMC, and elect the second place winner when App is the DMC winner, then (since DMC is immune from second place complaints) the resulting method can be described as follows without any mention of App: List the candidates in order

Re: [EM] MAMPO is probably better than MDDA

2007-03-19 Thread Forest W Simmons
Chris, this reminds me of something related I suggested last December in http://lists.electorama.com/pipermail/election-methods-electorama.com/2006-December/019070.html under the title of "[EM] carrying Warren's approval equilibrium idea to its logical conclusion" Here's an extract: "... Amo

Re: [EM] uses of truncation

2007-03-16 Thread Forest W Simmons
In my recent posting on this subject I mistakenly argued that if the truncation cutoff was uncovered, then it was also unbeaten. It is convenient to treat the truncation cutoff as a virtual candidate, "trunc." There are three cases to consider: Case 1. Trunc is the beats all candidate. Case

[EM] uses of truncation

2007-03-15 Thread Forest W Simmons
Various methods that make use of approval have alternative versions that use truncation as the approval cutoff. This suggests the concept of a virtual candidate "trunc" that is ranked below the lowest ranked real candidate on each ballot, but above any (and all) truncated candidates. How could

[EM] Beatpath(Unc, wv), a version of Beatpath that always picks from the Uncovered set

2007-03-13 Thread Forest W Simmons
Here's a version of Beatpath that always picks from the uncovered set: As in Beatpath(margins) or Beatpath(wv) we define a relation R on the candidates as follows: X R Y iff and only if there is a stronger beatpath from X to Y than from Y to X. This relation is transitive, and when there are n

[EM] UncDMC

2007-03-10 Thread Forest W Simmons
Here's a Monotone method (UncDMC) that chooses from the uncovered set, and always picks the DMC winner in the three candidate case: 1. List the candidates in approval order, highest to lowest, top to bottom. 2. Modify the list according to the following rule: as long as some candidate in the l

[EM] UncAAO, DMC, ASM, and TACC

2007-03-10 Thread Forest W Simmons
list) adds only those candidates to the chain that pairwise defeat each of the other candidates currently in the chain. How does TACC compare with ASM and DMC in other three candidate cases? Forest Chris Benham wrote: > >Forest W Simmons wrote: > >> Here's the quest

[EM] D2MAC

2007-03-10 Thread Forest W Simmons
Suppose that the alternatives are three restaurants for lunch, and the preferences of the two friends are: 1 Italian>Mexican>>Thai 1 Thai>Mexican>>Italian [The second voter seems to prefer hotter spices.] Under D2MAC they would always end up at a Mexican restaurant for lunch. This is fine if t

Re: [EM] MDDA vs UncAAO, ASM & DMC

2007-03-09 Thread Forest W Simmons
Mike O. wrote ... UncAAO, ASM, and DMC ignore defeat-magnitude and magnitude of pair-wise opposition. They look at pair-wise vote totals in order to find out who beats whom, but then they throw pair-wise vote total information away. Throwing that information away has regrettable consequences.

Re: [EM] Stronger than LIIA

2007-03-08 Thread Forest W Simmons
Compare: 1. Adding an alternative may not change the winner unless it pairwise defeats the old winner. 2. Adding an alternative may not change the winner unless it is an essential link in the strongest beatpath from the new winner to the old winner. As you mentioned , DMC satisfies (1). I th

Re: [EM] very simple email poll

2007-03-06 Thread Forest W Simmons
An observation on the ordinal version: 1 A>C>B 1 B>C>A If the method is clone free and neutral, then the clone sets B'={A,C} and A'={B,C} must have equal probability with B and A respectively. This implies that C must have zero probability. In the ratings version that Jobst specified in his s

Re: [EM] very simple email poll

2007-03-05 Thread Forest W Simmons
1. Is C socially preferable to A? ___Yes 2. Is tossing a coin to decide between A and B socially preferable to A? ___Yes 3. Is C socially preferable to tossing a coin to decide between A and B? ___No, although asymptotically the added variety of a lottery like (A+B+C)/3 might be preferable.

[EM] UncAAO defined in plain English

2007-03-03 Thread Forest W Simmons
andidate. This candidate is the winner. Forest Chris Benham wrote: > > >Forest W Simmons wrote: > >>UncAAO stands for Uncovered, Approval, Approval Opposition. Here's how >>it works: >> >>For each candidate X, >> >>if X is uncovered, >>

Re: [EM] UncAAO

2007-03-03 Thread Forest W Simmons
Mike, That's right. The C voters still have to use defensive strategy, but the moving the approval cutoff is sufficient. When there are only three candidates, UncAAO is the same as Smith Approval. Here's another classical example: 49 C 24 B>A 27 A>B Under wv, this is not a Nash Equilibrium,

Re: [EM] UncAAO

2007-03-02 Thread Forest W Simmons
Here are the main advantages of UncAAO over other Condorcet methods: 1. It is resistant to manipulation ... more so than Beatpath or Ranked Pairs, if I am not mistaken. 2. It always chooses from the uncovered set. 3. It is at least as easy as Ranked Pairs to describe. No mention of the pos

Re: [EM] UncAAO

2007-03-01 Thread Forest W Simmons
Forest wrote ... > >Is TACC monotone? It seems to me that the winner W could improve in >approval enough to overtake and surpass some W' in approval without >defeating W' pairwise, though W' covers W. I see: then W wouldn't have been the original winner. election-methods mailing list - s

Re: [EM] UncAAO

2007-03-01 Thread Forest W Simmons
Jobst, You've probably already figured this out, but here goes: UncAAO fails IDPA to the same extent that Approval does, because it is possible (however unlikely) for a Pareto Dominated alternative to get as much or more approval than an alternative that dominates it. But note that if Y' Pare

[EM] utilities, Gini, and lotteries

2007-02-27 Thread Forest W Simmons
Thanks to Jobst for clarifying the conditions under which various kinds of individual and social utilities can be justified. A most important idea is that for social utility the average of two lotteries could have more utility than either lottery separately because of the social value of having

[EM] UncAAO

2007-02-26 Thread Forest W Simmons
UncAAO stands for Uncovered, Approval, Approval Opposition. Here's how it works: For each candidate X, if X is uncovered, then let f(X)=X, else let f(X) be the candidate against which X has the least approval opposition, among those candidates that cover X. Start with the approval winner A

[EM] Proposal

2007-02-23 Thread Forest W Simmons
This is for those that didn't see this proposal buried in the details of a longer posting. There it was called method 1' . Here I'll call it UncAA for reasons that I will explain later: >From each covered candidate draw an arrow to the most approved candidate that covers it. Then start with

Re: [EM] MCA, MAMPO, etc.

2007-02-23 Thread Forest W Simmons
Chris B. should get more credit for MCA than I, since he has been more active in bringing it to the fore. What about 3-slot MAMPO? Which would be better, 3-slot MAMPO or the following hybrid of MCA and MAMPO? Ballots are 3-slot. If exactly one candidate gets into the highest slot on more than

Re: [EM] utility

2007-02-22 Thread Forest W Simmons
Warren remarked that when we drive our families across town we are risking their lives. I reply: If the purpose of the trip is not infinitely valuable compared to the value of one cent, then don't do it. Forest election-methods mailing list - see http://electorama.com/em for list info

Re: [EM] five monotonic methods ...

2007-02-22 Thread Forest W Simmons
Markus showed that some methods that pick from the uncovered set are not monotonic. In fact, it's easy to create non-monotonic methods, including (blush) the five that I recently claimed were monotonic. I found a subtle hole in my proof. The lemma is sound, but not quite sufficient to prove

Re: [EM] five monotonic methods that choose from the uncovered set

2007-02-21 Thread Forest W Simmons
I would like to mention that I proposed the first of these five methods back in December of 2004: http://lists.electorama.com/pipermail/election-methods-electorama.com/2004-December/014293.html "Ballots are ordinal with approval cutoff, equal rankings allowed. Let U(A) be the set of uncovered c

[EM] five monotonic ways to select winners from the uncovered set

2007-02-20 Thread Forest W Simmons
Candidate X covers candidate Y if and only if X defeats (pairwise) both Y and each candidate that Y defeats. An uncovered candidate is one that is not covered by any candidate. Method 1. If the approval winner A is uncovered, then elect A. Otherwise elect the highest

[EM] Borda and Honest Voters

2007-02-17 Thread Forest W Simmons
Mike, Don't forget that even with honest voters, Borda suffers from clone dependence in a major way. Forest election-methods mailing list - see http://electorama.com/em for list info

Re: [EM] A more efficient strategy-free ratings-based method than Hay voting

2007-02-13 Thread Forest W Simmons
Jobst, If I understand your method correctly, it is a refinement of the following method which is based on so called "ranked preferences" wherein the voters have some way of expressing their own relative preference strengths: Three ballots i, j, and k are drawn at random. Let A, B, and C desi

Re: [EM] A more efficient strategy-free ratings-based method than Hay voting

2007-02-12 Thread Forest W Simmons
Jobst, I'm still digesting your new method. It is starting to make sense to me. It is extremely creative and ingenious, in my opinion. I just hope that we haven't overlooked any subtle logical error. I have one question, though. If best strategy is to report true utilities, then what do you

Re: [EM] Hay Voting

2007-02-06 Thread Forest W Simmons
Here's a slightly different approach to Hay Voting: Suppose that a typical voter votes the range ballot v=[x1, x2, x3]. The ballot adds to the respective virtual accounts of the three candidates amounts of x1/r, x2/r, and x3/r , where r is the L_2 norm of the vector v. A dart board is co

Re: [EM] "Banzhaf Myth"

2007-02-05 Thread Forest W Simmons
Actually, in Mark Livingston's simulation at http://www.cs.unc.edu/~livingst/Banzhaf/#results he did assume that each state voted as a block. Perhaps you meant that the small population states voted together as a block? I can see where that is a possibility, since most of the small population

Re: [EM] Hay Voting

2007-02-03 Thread Forest W Simmons
I would like to express my admiration for the ingenuity of the Hay Voting method. In my opinion it is a great contribution to the theory of election methods. Forest election-methods mailing list - see http://electorama.com/em for list info

Re: [EM] Minmax under-representaton causes small-bias

2007-02-02 Thread Forest W Simmons
Here's the link to the data supporting the fact that the defacto super proportional representation of our small states is not enough to make up for their Banzhaf Voting Power deficiency: http://www.cs.unc.edu/~livingst/Banzhaf/#results Thanks, Forest election-methods mailing list - see

Re: [EM] What is good apportionment?

2007-02-02 Thread Forest W Simmons
Mike expressed concern about a bias in favor of the small states if we were to minimize maximum under representation. I would like to point out that even with their super proportional representation (due to the mandatory two senators) the small states are at a disadvantage in voting power. For

Re: [EM] FBC and ICC, when equal ranks are allowed

2007-01-29 Thread Forest W Simmons
I'm beginning to suspect that in the presence of equality and a reasonable definition of the ICC in that context, the AFB (FBC) and the ICC are compatible. Consider River, for example, where the drainage system is set up according to minimum opposition, i.e. the drainage follows the paths of l

Re: [EM] Problem solved (for pure ranked ballot)

2007-01-29 Thread Forest W Simmons
As Kevin pointed out in one of his posts I have been using a overly difficult standard of Favorite Betrayal. Here's a simpler proof based on the following definition of FBC: Raising favorite to top rank must not decrease expected utility. Given three voters with utilities consistent with the ra

Re: [EM] Problem solved (for pure ranked ballot)

2007-01-25 Thread Forest W Simmons
Here's a slightly simpler approach for a slightly weaker result. I show that (in the case of pure ordinal ballots) you cannot have all three of Monotonicity, Clone Independence, Pareto, and the Strong FBC. To be very careful we explicitly list the assumptions: 1. Strictly ranked ordinal ballots

Re: [EM] voting system design puzzle

2007-01-19 Thread Forest W Simmons
MCA satisfies both conditions (clone free and avoidance of favorite betrayal). It does use range style ballots, but it elects the candidate with the greatest median rating. If there are several candidates tied for greatest median rating, it elects the one with the greatest number of ballots th

Re: [EM] MCA

2007-01-18 Thread Forest W Simmons
Chris, as I remember, after MCA was invented various attempts at generalizing it eventually resulted in ER Bucklin (whole) for ranked ballots, even though strictly speaking (as you point out)that method is not a generalization of MCA. The nice thing about ER Bucklin (whole) was that it satisfi

[EM] GSA

2007-01-17 Thread Forest W Simmons
This method is based on ranked ballots that (at least) allow truncation. The candidate with the fewest truncations (i.e. the one that is ranked on the greatest number of ballots) is designated c0. Let c1 be the candidate (among those that cover c0) against which c0 scores the smallest oppositio