Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
Robert Bristow-Johnson wrote (9 Nov 2009): Of course IRV, Condorcet, and Borda use different methods to tabulate the votes and select the winner and my opinion is that IRV (asset voting, I might call it commodity voting: your vote is a commodity that you transfer according to your preferences) is a kabuki dance of transferred votes. and there is an *arbitrary* evaluation in the elimination of candidates in the IRV rounds: 2nd- choice votes don't count for shit in deciding who to eliminate (who decided that? 2nd-choice votes are as good as last-choice? under what meaningful and consistent philosophy was that decided?), then when your candidate is eliminated your 2nd-choice vote counts as much as your 1st-choice. These statements suggest a misunderstanding of how STV voting works and what preferences (US rankings) mean in the STV voting system. In all STV elections, the preferences are contingency choices. Your vote is transferred to your second choice only in the event that your first choice cannot secure election or does not need you support to secure election. This is most easily seen in single-winner STV elections (US = IRV), where the sequence of rounds is exactly analogous to the sequence of rounds in an exhaustive ballot (eliminating one candidate at a time in successive ballots). The only difference is that in an STV (IRV) election you don't know what all the other voters did in Round 1 when you come to give your second choice. So the preferences (= contingency choices) marked on an STV ballot are quite different from the preferences marked on, for example, a Borda ballot where some attempt will be made to use all of the information simultaneously. The same applies to STV multi-winner elections (STV-PR), though the connection is not so obvious in versions of STV that use fractional transfer values to remove the otherwise unavoidable element of chance. However, the contingency choice nature of the STV-PR preferences is obvious in those versions of STV-PR that use whole vote transfers, e.g. Cambridge MA and the Dáil Éireann. It is even more obvious in Thomas Hill's original application of STV-PR when the boys formed lines in the schoolyard to show their support for the various candidates. These STV preferences are all quite clearly contingency choices and they should not be interpreted in any other way. James Gilmour No virus found in this outgoing message. Checked by AVG - www.avg.com Version: 9.0.698 / Virus Database: 270.14.86/2533 - Release Date: 11/28/09 19:34:00 Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
Dear folks, there is another assumption in Arrow's theorem which people almost always forget: Determinism. Methods which use some amount of chance can easily meet all his other criteria, the most trivial example of this being again Random Ballot (i.e. pick a ballot uniformly at random and copy its ranking as the group's ranking). Some people think this violates the no-dictator requirement, but it doesn't since a dictator would be a person determined *beforehand*. Yours, Jobst Raph Frank schrieb: The theorem states (from wiki) that there is no method which has the following properties: * If every voter prefers X over Y, then the group prefers X over Y. * If every voter prefers X over Y, then adding Z to the slate won't change the group's preference of X over Y. * There is no dictator. All 3 of those conditions are met for range. The only problem is that adding Z could cause renormalisation changes in how people vote. A voter who votes A: 100 B: 0 might change vote to: A: 100 B: 50 Z: 0 after Z is added. Thus changing the difference between A and B for that ballot. Ranked systems allow full ranking. Adding another candidate just requires that you insert the candidate into the rank order. With range this might not be possible. If the candidate has a rating outside the max and min, a voter may have to rescale their prior preferences. If the assumption is that voters are just allowed add a rating for Z and not change any of their other ratings, then it meets the 3 conditions and thus is a counter example to Arrow's theorem. Election-Methods mailing list - see http://electorama.com/em for list info Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
At 12:22 PM 11/8/2009, Terry Bouricius wrote: A somewhat more accessible (and available online for free) analysis of strategic vulnerability of various methods is in this doctoral paper by James Green-Armytage (Strategic voting and Strategic Nomination: Comparing seven election methods). He found that Range and Approval were just about the worst in terms of manipulability. http://econ.ucsb.edu/graduate/PhDResearch/electionstrategy10b.pdf There is a great deal of confusion on the topic of strategic voting, based on a shift in the definition that took place after Brams suggested Approval Voting as strategy-free. Originally, strategic voting referred to expressing a preference contrary to one's sincere preference, in order to improve, in the eyes of the voter, the probability of a better outcome. In the context of ranked methods, the meaning was clear, and, for the most part, students of voting systems neglected the implications of equal ranking and the function of compromise in decision-making. In that context, there is something offensive about strategic voting, it seems dishonest. Yet strategic voting is how voters attempt to remedy defects in voting systems. The problem, if any, is in the voting system, not in the strategic voting itself. In a properly designed decision-making system, what we call strategic voting may facilitate a final decision or may postpone it, but would never harm the value of the outcome, unless it was a poor strategy that harms the outcome from the point of view of the voter, i.e., the voter would have been better off voting sincerely. It's clear that in the real world, people have strong preferences and weak preferences. When preference is weak, the voter may rationally decide to equally rank voters; I know that in real elections, I sometimes have difficulty deciding which of two candidates to vote for; an equal ranking there would be fully sincere, as an accurate expression of my preferences, and for me to prefer one over the other is actually insincere. Thus pure ranked voting systems force a kind of insincerity; equal ranking systems still allow the option of the expression of strict preference, so they only increase the options for expression open to the voter. However, what about the situation where a voter does have a preference between two candidates, but opts to equally rank them? In a Range system of adequate resolution, a fully sincere vote should be possible, without strategic harm to the voter's interests, but this needs definition, which is elusive. Practical Range systems, with limited resolution, resemble Approval voting, where preference strength below a certain level results in equal ranking. And preference strength is not independent of the voter's judgment of the strategic situation. I might prefer, say, Jan Kok for President, and I could write his name on the ballot, but there is a problem. I would prefer him, perhaps, to any candidate actually printed on the ballot, but if I rank him above one of the printed names, I'm almost certainly going to waste my vote. (Students of voting systems, again, have neglected the influence and implications of write-in votes, for, where write-in votes are possible, we could argue that most voters vote insincerely or strategically. They do not write in their true favorite because it would waste their vote, thus they rank one of the possible winners above their favorite, which meets the classical definition of strategic voting. I vote strategically so as to exercise maximum power from my right to vote, and this is, in fact, what we want voters to do, and what we should expect them to do. Voting is a method of making collective decisions, and collective decisions must necessarily involve, most of the time, some level of compromise, and compromise is strategic, wherein I approve an outcome even though it is not my first preference. The last classical neglect has been in the implications of majority approval or disapproval of an outcome. The study of voting systems has been focused on improving methods for making decisions from a single ballot. Major respect has been given to the Majority Criterion, because of basic democratic traditions, but there is no way to extract a majority-approved winner from a single ballot that is guaranteed to work, because the reality may be that there is no candidate approved by a majority. However, this problem was resolved long ago as to practical function: repeated balloting is used. Under Robert's Rules of Order, no election is valid unless approved by a majority of voters, and Robert's Rules does not allow restricting candidacies, i.e., the common runoff voting where the only eligible candidates in the runoff election are the top two from the primary, violates Robert's Rules, hence special bylaws are required if it is decided to implement this. However, a reasonable and not uncommon compromise is to print the names of
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
Abd ul-Rahman Lomax wrote: Notice that the requirement of Arrow that social preferences be insensitive to variations in the intensity of preferences was preposterous. Arrow apparently insisted on this because he believed that it was impossible to come up with any objective measure of preference intensity; however, that was simply his opinion and certainly isn't true where there is a cost to voting. Arrow doesn't impose that requirement; that's not what IIA says. -- Andrew Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
On Nov 16, 2009, at 10:53 AM, Andrew Myers wrote: Abd ul-Rahman Lomax wrote: Notice that the requirement of Arrow that social preferences be insensitive to variations in the intensity of preferences was preposterous. Arrow apparently insisted on this because he believed that it was impossible to come up with any objective measure of preference intensity; however, that was simply his opinion and certainly isn't true where there is a cost to voting. Arrow doesn't impose that requirement; that's not what IIA says. This is in part Arrow's justification for dealing only with ordinal (vs cardinal) preferences in the Possibility Theorem. Add may label it preposterous, but it's the widely accepted view. Mine as well. Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
On Nov 16, 2009, at 11:53 AM, Stéphane Rouillon wrote: Would this suggest it could be possible to overcome Arrow's theorem using range ballots? I do not want to say Arrow's theorem is false. All I ask is: Are prefential ballots one of the hypothesis used in Arrow's theorem proof? Because the context of Arrow's theorem is ordinal ballots, it doesn't apply (at least not directly) to range voting. Arrow felt that there were good and sufficient reasons to exclude cardinal preferences from consideration, and most social choice thinking has followed suit. That exclusion was not original with Arrow. From: jlund...@pobox.com Date: Mon, 16 Nov 2009 11:43:10 -0600 To: an...@cs.cornell.edu CC: election-meth...@electorama.com Subject: Re: [EM] Anyone got a good analysis on limitations of approval andrange voting? On Nov 16, 2009, at 10:53 AM, Andrew Myers wrote: Abd ul-Rahman Lomax wrote: Notice that the requirement of Arrow that social preferences be insensitive to variations in the intensity of preferences was preposterous. Arrow apparently insisted on this because he believed that it was impossible to come up with any objective measure of preference intensity; however, that was simply his opinion and certainly isn't true where there is a cost to voting. Arrow doesn't impose that requirement; that's not what IIA says. This is in part Arrow's justification for dealing only with ordinal (vs cardinal) preferences in the Possibility Theorem. Add may label it preposterous, but it's the widely accepted view. Mine as well. Election-Methods mailing list - see http://electorama.com/em for list info Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
Jonathan Lundell wrote: This is in part Arrow's justification for dealing only with ordinal (vs cardinal) preferences in the Possibility Theorem. Add may label it preposterous, but it's the widely accepted view. Mine as well. Arrow's Theorem seems like a red herring in the context of the cardinal vs. ordinal debate. IIA makes just as much sense when applied to range voting as it does to ranked voting. Arrow was just making a simplifying assumption and I don't see that it makes his results lose generality. -- Andrew Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
On Nov 16, 2009, at 2:15 PM, Andrew Myers wrote: Jonathan Lundell wrote: This is in part Arrow's justification for dealing only with ordinal (vs cardinal) preferences in the Possibility Theorem. Add may label it preposterous, but it's the widely accepted view. Mine as well. Arrow's Theorem seems like a red herring in the context of the cardinal vs. ordinal debate. IIA makes just as much sense when applied to range voting as it does to ranked voting. Arrow was just making a simplifying assumption and I don't see that it makes his results lose generality. I don't have his proof in front of me (I'm on the road), but I'm pretty sure that it assumes ordinal ranking. Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
Jonathan Lundell wrote: I don't have his proof in front of me (I'm on the road), but I'm pretty sure that it assumes ordinal ranking. It seems fairly obvious that the theorem also holds for ratings, because ratings can be projected onto rankings without affecting any of Arrow's criteria. To put it another way, the proofs I have seen all apply to range-based methods in a straightforward way--there needs to be some fiddling with the proof to deal with ties, but that issue is not essential. Letting voters give ratings doesn't mean you escape Arrow's Theorem. -- Andrew Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
The theorem states (from wiki) that there is no method which has the following properties: * If every voter prefers X over Y, then the group prefers X over Y. * If every voter prefers X over Y, then adding Z to the slate won't change the group's preference of X over Y. * There is no dictator. All 3 of those conditions are met for range. The only problem is that adding Z could cause renormalisation changes in how people vote. A voter who votes A: 100 B: 0 might change vote to: A: 100 B: 50 Z: 0 after Z is added. Thus changing the difference between A and B for that ballot. Ranked systems allow full ranking. Adding another candidate just requires that you insert the candidate into the rank order. With range this might not be possible. If the candidate has a rating outside the max and min, a voter may have to rescale their prior preferences. If the assumption is that voters are just allowed add a rating for Z and not change any of their other ratings, then it meets the 3 conditions and thus is a counter example to Arrow's theorem. Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
Strictly speaking I don't think Range is an election method according to Arrow, because you can't determine the winner from the orderings. It would be hard to make statements about the effect of introducing candidate Z when you don't have an assumption about what the outcome is based on. You can make it work if you want to I guess. Kevin Venzke Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
On Nov 16, 2009, at 4:58 PM, Raph Frank wrote: The theorem states (from wiki) that there is no method which has the following properties: * If every voter prefers X over Y, then the group prefers X over Y. * If every voter prefers X over Y, then adding Z to the slate won't change the group's preference of X over Y. * There is no dictator. All 3 of those conditions are met for range. The only problem is that adding Z could cause renormalisation changes in how people vote. The problem in applying the theorem to range isn't in the properties; it's in the formal definition of the method and the proof. http://en.wikipedia.org/wiki/Arrow%27s_impossibility_theorem#Formal_statement_of_the_theorem The proof applies to strict social welfare functions, defined as functions mapping a set of linear orderings (by voters) to a social ordering. While a range ballot (without ties) can be interpreted as a linear ordering, the range counting rule is not a function of that ordering, but rather of the cardinal values on the ballot. Different range ballots could have the same ordering but lead to a different result. Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting? (long)
On Nov 9, 2009, at 11:48 PM, Matthew Welland wrote: Approval Does not meet the desire of some to be able to differentiate between I like, I like a lot etc. (note: this seems like perfectionism to me. Large numbers of voters and opinions all over the bell curve should make individual expression at the greater level of granularity irrelevant.) we should be able to express our preferences. Approval reduces our metric of preference to a 1-bit number, a dichotomy. i would like to have more bits in that number. Suite of complicated systems that strive to reach Condorcet ideals. No regular bloke would ever trust 'em because you can't explain how they work in one or two sentences. Round Robin tournament, Ranked Ballot: The contestant who wins in a single match is the candidate who is preferred over the other in more ballots. The candidate who is elected to office is the contestant who loses to no one in the round robin tournament. that's two sentences and two labels. Technically superior to other systems. Not clear what problem with approval they would solve. Unless you are a perfectionist and insist that individuals express nuances of opinion... like which candidate they like better than the other candidate? It was very tedious voting in any of the ranking systems. it's tedious to decide who you like better? who you would prefer if any two candidates are presented? i will say this: even though it is prohibited in the present IRV that Burlington VT has, there is no reason that ties should not be allowed in any ranked ballot. but i would agree it would be tedious to allocate preference points in Range. So, to re-frame my question. What is the fatal flaw with approval? it's essentially like Plurality except you get to mark X on more than one candidate (like you do in multi-seat races). i don't like it for multi-seat (in the state senate for the county i am in, all of our senators are elected from the county at large and there are 6 for my county) i always think i'm hurting a candidate i actively support by voting for another candidate from the same party that i approve of. so then i mark X on only one candidate and, if enough people vote tactically like that, the election works like Plurality. we want an improvement to Plurality because we might like a three or four party system (or 3 parties and viable independents). we want to not have to consider the likelihood of wasting our vote by deciding who to Approve of. we know we approve of the candidate we support, but it is a tactical decision to decide if you approve of a candidate you would normally approve of but is not the candidate that you have actively supported. like what if you're a little old lady and you like and support you representative legislator for re-election. and you support him over any likely candidate from the other party, and it might be close so you wanna feel like you helped him. but your grandson that you cherish and are proud is running as an independent. in fact you gave money to your grandson's campaign. you support your grandson. you don't know if he'll win or not, but you do not want to harm his chances. you also don't want your good ol' incumbent you've always supported. you want to make sure he doesn't lose to the other major party candidate. but you wouldn't mind harming his chances if the race ended up between him and your grandson. is that putting it in an accessible context? so then with Approval voting, for sure this grandma marks X by her grandson's name. but does she or doesn't she Approve her good ol' incumbent? Approval doesn't let you mark it Approve except in the race with my top choice. I'm not interested in subtle flaws that result in imperfect results. I'm interested in flaws that result in big problems such as those we see with plurality and IRV. how 'bout electing the wrong candidate? i mean isn't that the essential flaw? e.g. the flaw with the Electoral College is that sometimes it elects the wrong candidate. it does pretty good when it selects the same winner as the popular vote, but when it disagrees with the popular vote it *never* creates more legitimacy or confidence in the election results. so then why have it? what good is it? it's either ineffective in filtering the popular vote or, when it *is* effective it makes matters worse. such a useful device! with Condorcet you elect the candidate that, from the set of voters who have an opinion, is preferred by a majority of that set over any other candidate that you pick. any winner of an election system that elects a candidate who is not the Condercet winner, has elected someone whom was rejected by the voting majority in favor of the Condorcet winner who wasn't elected. how is that congruent to the principle of democracy? do we have elections and explicitly give it to the candidate
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting? (long)
Dear Matthew, you wrote: Suite of complicated systems that strive to reach Condorcet ideals. 1. No regular bloke would ever trust 'em because you can't explain how they work in one or two sentences. Well, here's a very simple Condorcet system which can easily be explained in two sentences: 1. Let voters vote on candidate pairs, successively replacing the loser with a different candidate, in a random order of candidates. 2. As soon as all candidates have been included, the winner of the last pair is declared the overall winner. This system is arguably the earliest example of a Condorcet system. It was devised by Ramon Llull in the 13th century and was successfully used for elections in monastaries. It is easily understood by the common man since it resembles a procedure frequently used in child play. Yours, Jobst Matthew Welland schrieb: Thanks all for the discussion and pointers. I still can't concretely conclude anything yet but here are some rambling and random thoughts based on what was said and my prior experiences. Plurality 1. Leads to two lowest common denominator parties which are not accountable to the voters. This conclusion supported by real world observation. 2. Feels right to the non-critical mind, one man, one vote 3. Very fast at the polls Approval 1. Encourages participation of minor parties and thus should keep the big guys paying attention to a wider base. 2. Almost zero marginal implementation cost. Hanging chads count just fine :) 3. Understandable by anyone but feels wrong at first not fair, you get more than one vote. 4. Apparently has a terrible flaw but no one seems to be able to articulate it in layman terms. No real world experience available to illustrate the problem. Here is where I need to learn more. Data provided to date is unconvincing to me. 5. Does not meet the desire of some to be able to differentiate between I like, I like a lot etc. (note: this seems like perfectionism to me. Large numbers of voters and opinions all over the bell curve should make individual expression at the greater level of granularity irrelevant.) 6. Very fast at the polls. Pick yer favorites and head home for beer and telly. Range 1. Can break the vicious cycle of plurality 2. Not voting for someone at all can have a strong influence on election outcome. This is very non-intuitive and would take some getting used to. 3. Allows for nuanced voting. 4. Pain in the ass at the polls (relatively speaking). You can't safely disregard the candidates you don't care about so you *have* to assign everyone a ranking, possibly addressable by defaulting to zero for all candidates? This is considered a feature and I agree it has merit. But in reality it is a deal breaker for joe six pack and co. (and for lazy sobs like me). IRV 1. Demonstrably broken. 'nuff said. Suite of complicated systems that strive to reach Condorcet ideals. 1. No regular bloke would ever trust 'em because you can't explain how they work in one or two sentences. 2. Technically superior to other systems. 3. Not clear what problem with approval they would solve. Unless you are a perfectionist and insist that individuals express nuances of opinion... Some time ago I put together a site (primitive and unfinished[i]) to promote approval voting and in the process I spent a lot of time trying different systems on the web and repeatedly testing my own site. I noticed some interesting things from all that playing around. 1. It was very uncomfortable to go back to plurality after trying other systems. It feels unfair and broken. 2. It was very tedious voting in any of the ranking systems. 3. Approval felt boring but good. I have checked in on this list now and then and I admit I don't have the time or skills to follow all the arguments but it strikes me that approval voting is good enough to break the deadlock, at least in US politics and that it doesn't have any major flaws. The very understandable desire to be able to articulate in a finer grained way in your vote is perfectionism. With millions of voters, for every person on the fence about a particular candidate there will be some to either side who will essentially make or break the vote. If you are on the fence, approve or disapprove, it won't matter. So, to re-frame my question. What is the fatal flaw with approval? I'm not interested in subtle flaws that result in imperfect results. I'm interested in flaws that result in big problems such as those we see with plurality and IRV. [i] www.approvalvote.org Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting? (long)
Dear Robert, you wrote: Round Robin tournament, Ranked Ballot: The contestant who wins in a single match is the candidate who is preferred over the other in more ballots. The candidate who is elected to office is the contestant who loses to no one in the round robin tournament. that's two sentences and two labels. But it's incomplete as well... Yours, Jobst Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting? (long)
This method is also quite hand countable (unlike many other Condorcet methods). That was certainly an important feature in those days :-). It has some randomness in the results (when no Condorcet winner exists). Here's another one. Elect the candidate that wins all others in pairwise comparisons. If there is no such candidate, elect the one that needs least number of additional votes to win all others. (This is of course the famous minmax(margins) that I have promoted quite often.) Juho On Nov 10, 2009, at 12:57 PM, Jobst Heitzig wrote: Dear Matthew, you wrote: Suite of complicated systems that strive to reach Condorcet ideals. 1. No regular bloke would ever trust 'em because you can't explain how they work in one or two sentences. Well, here's a very simple Condorcet system which can easily be explained in two sentences: 1. Let voters vote on candidate pairs, successively replacing the loser with a different candidate, in a random order of candidates. 2. As soon as all candidates have been included, the winner of the last pair is declared the overall winner. This system is arguably the earliest example of a Condorcet system. It was devised by Ramon Llull in the 13th century and was successfully used for elections in monastaries. It is easily understood by the common man since it resembles a procedure frequently used in child play. Yours, Jobst Matthew Welland schrieb: Thanks all for the discussion and pointers. I still can't concretely conclude anything yet but here are some rambling and random thoughts based on what was said and my prior experiences. Plurality 1. Leads to two lowest common denominator parties which are not accountable to the voters. This conclusion supported by real world observation. 2. Feels right to the non-critical mind, one man, one vote 3. Very fast at the polls Approval 1. Encourages participation of minor parties and thus should keep the big guys paying attention to a wider base. 2. Almost zero marginal implementation cost. Hanging chads count just fine :) 3. Understandable by anyone but feels wrong at first not fair, you get more than one vote. 4. Apparently has a terrible flaw but no one seems to be able to articulate it in layman terms. No real world experience available to illustrate the problem. Here is where I need to learn more. Data provided to date is unconvincing to me. 5. Does not meet the desire of some to be able to differentiate between I like, I like a lot etc. (note: this seems like perfectionism to me. Large numbers of voters and opinions all over the bell curve should make individual expression at the greater level of granularity irrelevant.) 6. Very fast at the polls. Pick yer favorites and head home for beer and telly. Range 1. Can break the vicious cycle of plurality 2. Not voting for someone at all can have a strong influence on election outcome. This is very non-intuitive and would take some getting used to. 3. Allows for nuanced voting. 4. Pain in the ass at the polls (relatively speaking). You can't safely disregard the candidates you don't care about so you *have* to assign everyone a ranking, possibly addressable by defaulting to zero for all candidates? This is considered a feature and I agree it has merit. But in reality it is a deal breaker for joe six pack and co. (and for lazy sobs like me). IRV 1. Demonstrably broken. 'nuff said. Suite of complicated systems that strive to reach Condorcet ideals. 1. No regular bloke would ever trust 'em because you can't explain how they work in one or two sentences. 2. Technically superior to other systems. 3. Not clear what problem with approval they would solve. Unless you are a perfectionist and insist that individuals express nuances of opinion... Some time ago I put together a site (primitive and unfinished[i]) to promote approval voting and in the process I spent a lot of time trying different systems on the web and repeatedly testing my own site. I noticed some interesting things from all that playing around. 1. It was very uncomfortable to go back to plurality after trying other systems. It feels unfair and broken. 2. It was very tedious voting in any of the ranking systems. 3. Approval felt boring but good. I have checked in on this list now and then and I admit I don't have the time or skills to follow all the arguments but it strikes me that approval voting is good enough to break the deadlock, at least in US politics and that it doesn't have any major flaws. The very understandable desire to be able to articulate in a finer grained way in your vote is perfectionism. With millions of voters, for every person on the fence about a particular candidate there will be some to either side who will essentially make or break the vote. If you are on
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting? (long)
On Tuesday 10 November 2009 03:57:34 am you wrote: Dear Matthew, you wrote: Suite of complicated systems that strive to reach Condorcet ideals. 1. No regular bloke would ever trust 'em because you can't explain how they work in one or two sentences. Well, here's a very simple Condorcet system which can easily be explained in two sentences: 1. Let voters vote on candidate pairs, successively replacing the loser with a different candidate, in a random order of candidates. 2. As soon as all candidates have been included, the winner of the last pair is declared the overall winner. This system is arguably the earliest example of a Condorcet system. It was devised by Ramon Llull in the 13th century and was successfully used for elections in monastaries. It is easily understood by the common man since it resembles a procedure frequently used in child play. That is an excellent description. Thanks. I've always liked that specific system and think being Condorcet compliant makes great sense in smaller elections or where a perfect choice is critical. Implementing it on a large scale seems tough and actually voting in it seems tedious. If there are N candidates am I forced to make N-1 decisions? If there is a short circuit way to do the vote then it might be workable. The improvement over approval still seems marginal, especially in large elections and I think the cost for implementing, tabulating and voting is much higher, Yours, Jobst Matthew Welland schrieb: Thanks all for the discussion and pointers. I still can't concretely conclude anything yet but here are some rambling and random thoughts based on what was said and my prior experiences. Plurality 1. Leads to two lowest common denominator parties which are not accountable to the voters. This conclusion supported by real world observation. 2. Feels right to the non-critical mind, one man, one vote 3. Very fast at the polls Approval 1. Encourages participation of minor parties and thus should keep the big guys paying attention to a wider base. 2. Almost zero marginal implementation cost. Hanging chads count just fine :) 3. Understandable by anyone but feels wrong at first not fair, you get more than one vote. 4. Apparently has a terrible flaw but no one seems to be able to articulate it in layman terms. No real world experience available to illustrate the problem. Here is where I need to learn more. Data provided to date is unconvincing to me. 5. Does not meet the desire of some to be able to differentiate between I like, I like a lot etc. (note: this seems like perfectionism to me. Large numbers of voters and opinions all over the bell curve should make individual expression at the greater level of granularity irrelevant.) 6. Very fast at the polls. Pick yer favorites and head home for beer and telly. Range 1. Can break the vicious cycle of plurality 2. Not voting for someone at all can have a strong influence on election outcome. This is very non-intuitive and would take some getting used to. 3. Allows for nuanced voting. 4. Pain in the ass at the polls (relatively speaking). You can't safely disregard the candidates you don't care about so you *have* to assign everyone a ranking, possibly addressable by defaulting to zero for all candidates? This is considered a feature and I agree it has merit. But in reality it is a deal breaker for joe six pack and co. (and for lazy sobs like me). IRV 1. Demonstrably broken. 'nuff said. Suite of complicated systems that strive to reach Condorcet ideals. 1. No regular bloke would ever trust 'em because you can't explain how they work in one or two sentences. 2. Technically superior to other systems. 3. Not clear what problem with approval they would solve. Unless you are a perfectionist and insist that individuals express nuances of opinion... Some time ago I put together a site (primitive and unfinished[i]) to promote approval voting and in the process I spent a lot of time trying different systems on the web and repeatedly testing my own site. I noticed some interesting things from all that playing around. 1. It was very uncomfortable to go back to plurality after trying other systems. It feels unfair and broken. 2. It was very tedious voting in any of the ranking systems. 3. Approval felt boring but good. I have checked in on this list now and then and I admit I don't have the time or skills to follow all the arguments but it strikes me that approval voting is good enough to break the deadlock, at least in US politics and that it doesn't have any major flaws. The very understandable desire to be able to articulate in a finer grained way in your vote is perfectionism. With millions of
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting? (long)
On Nov 10, 2009, at 7:58 AM, Matthew Welland wrote: On Tuesday 10 November 2009 03:57:34 am you wrote: Dear Matthew, you wrote: Suite of complicated systems that strive to reach Condorcet ideals. 1. No regular bloke would ever trust 'em because you can't explain how they work in one or two sentences. Well, here's a very simple Condorcet system which can easily be explained in two sentences: 1. Let voters vote on candidate pairs, successively replacing the loser with a different candidate, in a random order of candidates. 2. As soon as all candidates have been included, the winner of the last pair is declared the overall winner. This system is arguably the earliest example of a Condorcet system. It was devised by Ramon Llull in the 13th century and was successfully used for elections in monastaries. It is easily understood by the common man since it resembles a procedure frequently used in child play. That is an excellent description. Thanks. Gives a feel for something good enough for their purposes - if there is a CW the CW wins. BUT, if there is a cycle, the best candidate can lose to another cycle member - so better make sure the apparent CW gets compared with every other candidate. I've always liked that specific system and think being Condorcet compliant makes great sense in smaller elections or where a perfect choice is critical. Implementing it on a large scale seems tough and actually voting in it seems tedious. If there are N candidates am I forced to make N-1 decisions? If there is a short circuit way to do the vote then it might be workable. In voting you could start with thinking who you would approve of. Then vote for them, while ignoring the others that you like less. Do any of: Approve them by giving them the same rank. Vote for the best as in FPTP. Rank them to show your preference for better vs lesser. The improvement over approval still seems marginal, especially in large elections and I think the cost for implementing, tabulating and voting is much higher, Agreed the implementing costs - mostly in being able to do this. With the ability you get a big help in some elections and less or little in others (like 0 when only two candidates). Tabulating a ballot gets to be labor when a voter ranks many candidates. Being able to determine winner from the N*N array was an implementing cost, but then easy to do via computer (assuming use of an easy variant of Condorcet). Voters who were happy with FPTP will see no benefit - but no cost once they see they can vote as they have before. Voters who have studied range/score will make two groups: sad to be unable to express the exact size of their likes/dislikes; thankful for the easier decisions involved here. Voters who want to rank higher those they like best will be thankful to get past approval. Dave Ketchum Yours, Jobst Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting? (long)
Thanks all for the discussion and pointers. I still can't concretely conclude anything yet but here are some rambling and random thoughts based on what was said and my prior experiences. Plurality Leads to two lowest common denominator parties which are not accountable to the voters. This conclusion supported by real world observation. Feels right to the non-critical mind, one man, one vote Very fast at the polls Approval Encourages participation of minor parties and thus should keep the big guys paying attention to a wider base. Almost zero marginal implementation cost. Hanging chads count just fine :) Understandable by anyone but feels wrong at first not fair, you get more than one vote. Apparently has a terrible flaw but no one seems to be able to articulate it in layman terms. No real world experience available to illustrate the problem. Here is where I need to learn more. Data provided to date is unconvincing to me. Does not meet the desire of some to be able to differentiate between I like, I like a lot etc. (note: this seems like perfectionism to me. Large numbers of voters and opinions all over the bell curve should make individual expression at the greater level of granularity irrelevant.) Very fast at the polls. Pick yer favorites and head home for beer and telly. Range Can break the vicious cycle of plurality Not voting for someone at all can have a strong influence on election outcome. This is very non-intuitive and would take some getting used to. Allows for nuanced voting. Pain in the ass at the polls (relatively speaking). You can't safely disregard the candidates you don't care about so you *have* to assign everyone a ranking, possibly addressable by defaulting to zero for all candidates? This is considered a feature and I agree it has merit. But in reality it is a deal breaker for joe six pack and co. (and for lazy sobs like me). IRV Demonstrably broken. 'nuff said. Suite of complicated systems that strive to reach Condorcet ideals. No regular bloke would ever trust 'em because you can't explain how they work in one or two sentences. Technically superior to other systems. Not clear what problem with approval they would solve. Unless you are a perfectionist and insist that individuals express nuances of opinion... Some time ago I put together a site (primitive and unfinished[i]) to promote approval voting and in the process I spent a lot of time trying different systems on the web and repeatedly testing my own site. I noticed some interesting things from all that playing around. It was very uncomfortable to go back to plurality after trying other systems. It feels unfair and broken. It was very tedious voting in any of the ranking systems. Approval felt boring but good. I have checked in on this list now and then and I admit I don't have the time or skills to follow all the arguments but it strikes me that approval voting is good enough to break the deadlock, at least in US politics and that it doesn't have any major flaws. The very understandable desire to be able to articulate in a finer grained way in your vote is perfectionism. With millions of voters, for every person on the fence about a particular candidate there will be some to either side who will essentially make or break the vote. If you are on the fence, approve or disapprove, it won't matter. So, to re-frame my question. What is the fatal flaw with approval? I'm not interested in subtle flaws that result in imperfect results. I'm interested in flaws that result in big problems such as those we see with plurality and IRV. [i] www.approvalvote.org Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
Matthew, I'm not sure if it is quite at the layman level, but Prof. Nicloaus Tideman's recent book Collective Decisions and Voting has an analysis of vulnerability to strategic manipulation of virtually every single-winner voting method that has ever been proposed and concludes that Range Voting along with Borda and four other methods have defects that are so serious as to disqualify them from consideration. (page 238). Range Voting advocates on this list dispute his definition of resistance to strategy. A somewhat more accessible (and available online for free) analysis of strategic vulnerability of various methods is in this doctoral paper by James Green-Armytage (Strategic voting and Strategic Nomination: Comparing seven election methods). He found that Range and Approval were just about the worst in terms of manipulability. http://econ.ucsb.edu/graduate/PhDResearch/electionstrategy10b.pdf Terry Bouricius - Original Message - From: Matthew Welland m...@kiatoa.com To: Election Methods Mailing List election-meth...@electorama.com Sent: Saturday, November 07, 2009 3:12 PM Subject: [EM] Anyone got a good analysis on limitations of approval andrange voting? It seems to me that approval and range voting eliminate most of the strategic opportunity in single winner elections and the marginal improvement of other methods is fairly small. Can anyone point me to analysis, preferably at a layman level, that contradicts or supports this assertion? Or, in succinct terms, what are the strategic flaws in approval or range voting? Thanks, Matt -=- Election-Methods mailing list - see http://electorama.com/em for list info Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
On Sun, Nov 8, 2009 at 5:22 PM, Terry Bouricius ter...@burlingtontelecom.net wrote: A somewhat more accessible (and available online for free) analysis of strategic vulnerability of various methods is in this doctoral paper by James Green-Armytage (Strategic voting and Strategic Nomination: Comparing seven election methods). He found that Range and Approval were just about the worst in terms of manipulability. http://econ.ucsb.edu/graduate/PhDResearch/electionstrategy10b.pdf His assumptions about how people vote are not very realistic. Plurality - vote for favourite Top 2 - run-off - vote for favourite and then best of top 2 Alternative vote - honest ranking Minimax - honest ranking Borda - honest ranking Approval - vote for better than mean Range - give max to favourite and min to least favourite and scale the rest His analysis is pretty interesting and he has created a condition for each method that is needed for the winner to be vulnerable to loss if a group of voters switched their vote. In practice, people are able to handle the basics of plurality strategy. It would be interesting to see how approval scores with a pre-election poll being performed. For example, each voter approves based on a mean threshold and then use the result of that election to work out the top-2. Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
Terry and Matthew, Terry Bouricius wrote: I'm not sure if it is quite at the layman level, but Prof. Nicloaus Tideman's recent book Collective Decisions and Voting has an analysis of vulnerability to strategic manipulation of virtually every single-winner voting method that has ever been proposed... He leaves out the methods that facilitate communication among the voters, namely liquid democracy, delegable proxy or delegate cascade. These are all forms of continuous, peer-to-peer voting. Their overall are difficult to manipulate, except by force of reason. (This assumes that all votes/voters are public.) These methods are not proof against micro-strategy by individual voters, but their combined effects cannot significantly sway the overall results (not in theory, anyway). A somewhat more accessible (and available online for free) analysis of strategic vulnerability of various methods is in this doctoral paper by James Green-Armytage (Strategic voting and Strategic Nomination: Comparing seven election methods). He found that Range and Approval were just about the worst in terms of manipulability. http://econ.ucsb.edu/graduate/PhDResearch/electionstrategy10b.pdf He makes the same omission, at least in that paper. Please, does anyone know where Green-Armytage analyzes his liquid democracy from the angle of strategic voting? Matthew Welland wrote: It seems to me that approval and range voting eliminate most of the strategic opportunity in single winner elections and the marginal improvement of other methods is fairly small. Can anyone point me to analysis, preferably at a layman level, that contradicts or supports this assertion? Or, in succinct terms, what are the strategic flaws in approval or range voting? In that they encourage voters to be manipulative. In terms of action theory, these voting methods (and almost all others) are tools of strategic action. The voter uses them in an attempt to attain a preconceived end. So they are tools of *teleological* action. But to attain the preconceived end, the voter must calculate on the behaviour of other voters. This introduces a social aspect to the action, which is therefore subclassed as *strategic* action. The only alternative in this context is *communicative* action. In communicative action, the voters coordinate their voting behaviour by discussion that is aimed at mutual understanding and consensus. Ordinary voting methods do not support this.^[2] For this you need a communicative method, such as continuous, peer-to-peer voting (top). [1] I'm not sure that the terminology aligns perfectly with voting theory. Action theory is from sociology: Jürgen Habermas. 1981. The Theory of Communicative Action. Volume 1. Reason and Rationalization of Society. Translated by Thomas McCarthy, 1984. Beacon Hill, Boston. pp. 75-101. [2] Not only do these voting methods not support communicative action, but they serve as substitutes for it. They are therefore defined as steering media. The archetypal steering medium is money, which serves as a substitute for inter-communicative bartering. [ref. Vol. 2 of above] -- Michael Allan Toronto, 647-436-4521 Skype michael_c_allan http://zelea.com/ Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Anyone got a good analysis on limitations of approval andrange voting?
On Nov 8, 2009, at 8:43 PM, Raph Frank wrote: On Sun, Nov 8, 2009 at 5:22 PM, Terry Bouricius ter...@burlingtontelecom.net wrote: A somewhat more accessible (and available online for free) analysis of strategic vulnerability of various methods is in this doctoral paper by James Green-Armytage (Strategic voting and Strategic Nomination: Comparing seven election methods). He found that Range and Approval were just about the worst in terms of manipulability. http://econ.ucsb.edu/graduate/PhDResearch/electionstrategy10b.pdf His assumptions about how people vote are not very realistic. There are many small things in the paper that can be discussed but I think he gives a good solid basis for further discussions and improvements to make the results more accurate from real life modelling point of view. This is a good attempt to describe the practical properties of various methods from a neutral scientific point of view. Plurality - vote for favourite Top 2 - run-off - vote for favourite and then best of top 2 Alternative vote - honest ranking Minimax - honest ranking Borda - honest ranking Approval - vote for better than mean Two short comments on this one. - One could alternatively assume that sincere voting in Approval would already be (at least partially) based on applying the basic strategy of trying to make a difference between the (two, three) most probable winners. Strategic voting would mean additional strategies on top of the basic one. - Unfortunately the model that James Green-Armytage used was not yet able to handle strategic nominations in Approval. I think cloning has an impact in Approval (clones may easily harm you). Juho Range - give max to favourite and min to least favourite and scale the rest His analysis is pretty interesting and he has created a condition for each method that is needed for the winner to be vulnerable to loss if a group of voters switched their vote. In practice, people are able to handle the basics of plurality strategy. It would be interesting to see how approval scores with a pre-election poll being performed. For example, each voter approves based on a mean threshold and then use the result of that election to work out the top-2. Election-Methods mailing list - see http://electorama.com/em for list info Election-Methods mailing list - see http://electorama.com/em for list info
