On Fri, 21 Dec 2007 10:57:01 -0800 Ian Fellows wrote: > Dave > "I see Borda as more complex, without offering benefits to justify the cost. > I do not see counting Borda as a flavor of Condorcet." > > The Borda count is not a flavor of Condorcet, but when it is done by runoff > (i.e. iterative deletion of the lowest borda count) then it is a condorcet > method.
See if I understand well enough to describe a trial run: 48 B X G N 24 N G X B 25 G N X B Score: B 144=48*3 G 171=48*1 24*2 25*3 N 122=24*3 25*2 X 145=48*2 24*1 25*1 Next step: B 96=48*2 G 98=24*2 25*2 X 97=48 24 25 So B loses and G wins. > > The basic thrust of my thought was that people seem willing to accept IRV as > a method of single winner determination. But it has serious weaknesses > compared to other rank ballot measure. On the other hand, it is very simple, > and easy for people to understand: The standard method of describing IRV skips its problem of failures due to not looking at all that the ballot says - so implied understanding aids its acceptance without bothering with true understanding. > > Electing a candidate using IRV proceeds as follows: > Step 1: All 1st place votes for each candidate are counted > Step 2: The candidate with the lowest count is eliminated, and the 1st place > votes are recalculated using only the non-eliminated candidates > Step 3: If only one candidate is left, she is declared the winner; otherwise > step 2 is repeated > > Most condorcet methods are much more conceptually difficult, requiring the > voter to think about all pair wise relationships in order to figure out how > their ballot effects the outcome. Baldwin's method, is just as simple as > IRV. note: I prefer a descriptive name for the method Total Points Runoff > (TPR). I DO NOT understand your words. I described what the voter needs to know to use Condorcet - make a list of as many of the candidates as you wish to vote for, sort your list in priority order, and vote, indicating which you like the most. What I understand of Borda indicates it has the same requirement, except Borda seems to exclude voting for two candidates with indicated equal liking. > > Electing a candidate using TPR proceeds as follows: > Step 1: The total points for each candidate is found > Step 2: The candidate with the lowest number of points is eliminated, and > the points are recalculated using only the non-eliminated candidates > Step 3: If only one candidate is left, she is declared the winner; otherwise > step 2 is repeated > > "Cycles are a Condorcet complication. Not expectable too often, for they > result from 3 or more candidates approaching a conflicting tie for winning - > such as A>B>G>A." > > Also, if you don't expect cycles to occur too often, then Condorcet methods > have very nice properties: > TPR satisfies the following Criteria: > 1. Condorcet winner > 2. Condorcet loser > 3. Smith set > 4. Majority > 5. Mutual majority > 6. Reversal Symmetry > 7. Pareto > 8. Universality > 9. Non-imposition > 10. Non-dictatorship > 11. Resolvability > > It can also be shown that if there is a condorcet winner: > 1. TPR is monotonic > 2. TPR is independent of clones. > 3. TPR is independent of irrelevant alternatives > 4. TPR is invulnerable to compromise > 5. TPR is invulnerable to favorite betrayal > > TPR is also resistant to burying, in that if there is a condorcet winner, a > voter insincerely burying (giving a low ranking) a candidate will lead to > three possible outcomes: > 1. The condorcet winner will still be the winner > 2. A candidate less favorable to the voter will be the winner > 3. the smith set will contain the condorcet winner, and candidates both > less, and more favorable to the voter than the condorcet winner. > > Thus either the burying makes no difference, or it is against the voters > interest, or it is very risky because the smith set contains both more > favorable, and less favorable candidates. Thus, because small changes in > voter preferences can change which candidate is chosen within the smith set, > the voter would be taking a big risk that his more favorable candidate would > be chosen from the smith set, verses the less favorable candidate that he > buried the condorcet winner behind. > > > cheers, > Ian > > > > -----Original Message----- > From: Dave Ketchum [mailto:[EMAIL PROTECTED] > Sent: Thursday, December 20, 2007 7:47 PM > To: Ian Fellows > Cc: Election Methods Mailing List > Subject: Re: [Election-Methods] Borda-elimination, a Condorcet method > for public elections? > > > "Condorcet" caught my eye - I think it deserves more attention but do not > know how to get there. > > I see Borda as more complex, without offering benefits to justify the > cost. I do not see counting Borda as a flavor of Condorcet. > > Answering your questions: > 1- Condorcet is understandable if properly presented to voters and > public. > 2- Still Condorcet. > 3- What is really that much better than Condorcet (based on what a > voter normally knows on election day - all kinds of nonsense can be based > on knowing what all others are doing, with your own plotting kept secret). > Remember that Range allows stating numeric ratings - for which > it must demand that the voter ASSIGN numeric ratings. > I see Range as competitive, deserving careful analysis of > differences - perhaps mixed with true comparison by voters. > > Voting: > Rank one or more candidates, thus indicating liking them better than > the sea of unranked candidates. > Use higher ranks for better liking (see voter instructions as to > whether 3 is higher or lower than 4, as a rank). > Equal ranks are permissible for equal liking. > If, for example, you only wish to rank a couple, 4&5 would have the > same meaning as 1&7 - it is relative values that matter, not magnitude of > rank difference. > If, for example, you like neither of the most likely winners, smart > to rank at least one such, unless you see them deserving to tie. > > Analyzing results: > Results are publishable for whatever parts of a district are counted, > looking much as a tournament score, giving results for each pair of > candidates. > > Cycles are a Condorcet complication. Not expectable too often, for they > result from 3 or more candidates approaching a conflicting tie for winning > - such as A>B>G>A. > > On Thu, 20 Dec 2007 11:37:15 -0800 Ian Fellows wrote: > >>Hi all, >> >> I've been thinking a bit lately about the lack of Condorcet methods in >>public elections. I have written a rough outline of why Borda-elimination >>(Baldwin) is an attractive option for implementation in the public sphere. >> >>If you are interested, check out: >>http://thefell.googlepages.com/statisticalsnipstprelections >> >>Does anyone have thoughts on why Condorcet methods have not been used more >>often? Are there proponents here of different winner criteria (i.e. > > Borda), > >>or is there a relatively strong consensus that if a Condorcet winner > > exists > >>he should be elected? If so, what methodology do you think is 1. >>understandable by the public, 2. Theoretically justifiable, 3. Resistant > > to > >>tactical voting >> >>Cheers, >> >>Ian Fellows >>Statistician >>University of California, San Diego >>http://thefell.googlepages.com/ -- [EMAIL PROTECTED] people.clarityconnect.com/webpages3/davek Dave Ketchum 108 Halstead Ave, Owego, NY 13827-1708 607-687-5026 Do to no one what you would not want done to you. If you want peace, work for justice. ---- Election-Methods mailing list - see http://electorama.com/em for list info