Re: [EM] Continuous bias
On 16.5.2011, at 15.49, Markus Schulze wrote: > Hallo, > > currently, there is the tradition to give 12, 10, 8 points > always to its political/ethnic/geographic neighbours. I recommend > that a Condorcet method should be used to reduce the effects of > this voting behaviour. As Condorcet methods put less emphasis on > first preferences, the above voting behaviour would be nivellated > over all countries. > > Markus Schulze Yes, Condorcet methods might be good. Also Borda seems to be quite good in the Eurovision context since I have not heard of countries giving 0 points to good songs that are so good that they might threaten their victory of their favourite songs or their favourite countries (with bad songs). The usual Borda strategies are thus probably not used. Range style methods would be more problematic since all the points could be given to few favourites. Condorcet and other ranking based methods may also be vulnerable to continuous bias. I was trying to find some defence also against one country always ranking some other country first. Similar factors could be counted and the weight of the pairwise preferences of the favoured countries (over others) could be reduced (I mentioned this shortly in the initial mail too). The current method gives high points only to ten best songs. It thus emphasizes the impact of being among the few best songs. Condorcet could support also songs that all find acceptable but not spectacular (=among the top ten). I don't believe this difference would make a big impact anyway. Condorcet would be a good method for Eurovision. It would not eliminate the continuous bias problem very efficiently though. (And as already noted few times, there may not be any need to reduce that continuous bias in the Eurovision Song Contest in the first place.) Condorcet counting process is a bit more difficult to follow than the Borda (or Range) counting process. That may make it a bit less fun in big real-time shows like the Eurovision Song Contest. (Note that votes needed to beat all the others could be a nice way to indicate the state of the vote calculation process to the real-time audience of millions of viewers. :-) Juho Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Continuous bias
On 16.5.2011, at 15.30, Kristofer Munsterhjelm wrote: > Juho Laatu wrote: >> The final of the Eurovision Song Contest of this year was held last >> saturday. In the vote all countries give points to the songs of all >> other countries (that made it to the final). The voting traditions >> are a bit biased. Countries tend to give high points to their >> neighbours or otherwise similar countries. Countries are not allowed >> to vote for themselves, but minorities living or working in some >> country may have considerable impact since they may have sympathies >> also towards some other country. All this means that in addition to >> voting for good songs people vote also for their best friends. >> Eurovision Song Contest is a friendly competition though, and a major >> carnival, and people don't worry too much about this kind of (well >> known) voting patterns. Maybe they are just part of the fun and even >> one essential part of the competition. But as a person interested in >> voting I started wondering if this kind of voting patterns could be >> fixed or eliminated. > (...) >> Would this approach maybe be useful and practical somewhere? What >> other approaches there are to eliminate this kind of systematical >> bias? > > There's a problem with this sort of blind compensation, because the method > itself can't know whether the bias is because a country is consistently good > or because the other countries consistently favor that country. If the country is consistently good, then all countries should give it lots of points. In that case the factors will remain low for all countries. They will get higher only if someone gives (continuously) more points to some song than others do. The given vote is thus compared to the average result of that song only (not to the average points of all the other songs, which is a constant number). > > Say, for instance, that country X somehow gets very good at making Eurovision > songs, so it wins a lot more often than would be expected by chance. Then > your compensation scheme would make it harder for X to win; X is punished, > ratchet effect style, for being good. It gets even more blurry when you > consider that the countries reward each other according to "popularity" - > perhaps the people of the Eastern European countries like the kind of music > they themselves make, for instance, so that the "bias" is indirect rather > than direct? Let's say some country makes good songs, and it will get 12, 10 or 8 points from most countries every year. It gets maybe 10 points on average from all the other countries. In that situation a country that gives it 12 points gets a factor of 1.2 which is very low. So, support of good songs will not be punished (or only very lightly). On the other hand giving 12 points to a country that gets on average 0.5 points several years in a row yields a high factor (24). Voting for bad songs is thus a more likely way to gain high factors (for that country with bad songs). It is true that the method to some extent punishes Eastern European countries for liking "eastern style" songs. Is not the intention of the method to punish for sincere musical opinions. Probably that factor is however not high if Eastern European countries support each others as a (reasonably) unified group. Within a group is is also not possible to give all countries 12 points in the Borda like method of the Eurovision Song Contest. Note also that the assumption that the Eastern European countries support their own songs more than the Western European countries do already implies that the Western European countries must prefer their own songs. They will thus be equally punished, which makes the method neutral again. The next problem is what happens if different "blocks" are of different size. In the case that the size of some (sincere musical) blocks is two, they will be punished more. But still they would (usually) be punished less than in the case of strategic support between the two countries since in the strategic (/friendly) case the quality of the songs would have no impact on the points given to each others. (The factors will be low if their points vary according to the quality of the song.) The method thus relies on that it is not a common case that one country always likes the songs of another country (good or bad from and good or bad from the point of view of all the countries). Even if that happens, this probably does not have much impact on who wins. It would be however good not to unnecessarily reduce the points of any country. But it is not easy to separate strategic voting from sincere constant and song quality independent to some country. In the Eurovision Song Contest countries tend to produce songs that are liked in all the participating countries (also this fact has been criticized). The Eurovision Song Contest thus does not probably suffer too much from this phenomenon. But there might be other elections where
Re: [EM] Continuous bias
Hallo, currently, there is the tradition to give 12, 10, 8 points always to its political/ethnic/geographic neighbours. I recommend that a Condorcet method should be used to reduce the effects of this voting behaviour. As Condorcet methods put less emphasis on first preferences, the above voting behaviour would be nivellated over all countries. Markus Schulze Election-Methods mailing list - see http://electorama.com/em for list info
Re: [EM] Continuous bias
Juho Laatu wrote: The final of the Eurovision Song Contest of this year was held last saturday. In the vote all countries give points to the songs of all other countries (that made it to the final). The voting traditions are a bit biased. Countries tend to give high points to their neighbours or otherwise similar countries. Countries are not allowed to vote for themselves, but minorities living or working in some country may have considerable impact since they may have sympathies also towards some other country. All this means that in addition to voting for good songs people vote also for their best friends. Eurovision Song Contest is a friendly competition though, and a major carnival, and people don't worry too much about this kind of (well known) voting patterns. Maybe they are just part of the fun and even one essential part of the competition. But as a person interested in voting I started wondering if this kind of voting patterns could be fixed or eliminated. (...) Would this approach maybe be useful and practical somewhere? What other approaches there are to eliminate this kind of systematical bias? There's a problem with this sort of blind compensation, because the method itself can't know whether the bias is because a country is consistently good or because the other countries consistently favor that country. Say, for instance, that country X somehow gets very good at making Eurovision songs, so it wins a lot more often than would be expected by chance. Then your compensation scheme would make it harder for X to win; X is punished, ratchet effect style, for being good. It gets even more blurry when you consider that the countries reward each other according to "popularity" - perhaps the people of the Eastern European countries like the kind of music they themselves make, for instance, so that the "bias" is indirect rather than direct? I think the proper way to do this, if getting rid of bias were to be important, would be to make a video (or audio) recording of each country's song and then play it without saying what country it is. The countries then rate based on that alone, and the country names are revealed afterwards. However, there are many ways to "smuggle" information through audio and particularly video, so it would only weaken the effect. Besides, it would affect the circus aspect of the Eurovision Song Contest, and would be nearly impossible since the ESC has multiple rounds. Alternatively, one could use strategy-resistant methods: median ratings if cardinal, or something like the "IRV until there's a CW" method if ordinal, so that the actual effect of this kind of bias is weakened further. Borda is very manipulable, and I expect the Eurovision variant isn't far off Borda level, either. (I can't really see Eurovision doing the Condorcet-IRV method though: "Let's see if there's a pairwise champion among those who remain! No? Oh well, too bad, Germany: you're out!". :p) Election-Methods mailing list - see http://electorama.com/em for list info
[EM] Continuous bias
The final of the Eurovision Song Contest of this year was held last saturday. In the vote all countries give points to the songs of all other countries (that made it to the final). The voting traditions are a bit biased. Countries tend to give high points to their neighbours or otherwise similar countries. Countries are not allowed to vote for themselves, but minorities living or working in some country may have considerable impact since they may have sympathies also towards some other country. All this means that in addition to voting for good songs people vote also for their best friends. Eurovision Song Contest is a friendly competition though, and a major carnival, and people don't worry too much about this kind of (well known) voting patterns. Maybe they are just part of the fun and even one essential part of the competition. But as a person interested in voting I started wondering if this kind of voting patterns could be fixed or eliminated. The winner is chosen using a Borda like method. Each country gives points to 10 songs that they consider best. Those songs are given 12, 10, 8, 7, 6, 5, 4, 3, 2 and 1 points. In the final there have been 25 or 24 songs, so all the remaining songs will get 0 points. Then the points are summed up and the song/country with most points wins. I compared the number of points that each country gave to each other country to the average number of points that that country got. After checking few previous years the patterns were quite obvious. The basic fix to the problem could be such that if country A gives on average k times as much points to country B than others do, then the points given by country A to country B in the next election will be divided by n. One could make this function also softer in the sense that one would not reduce the points that much, or one would put higher weight on the few last years only, or giving low points once would be considered a proof that the pattern is not systematic (and that would reduce the factor more that giving high points increases it). But I guess the basic idea is clear. Systematic positive bias leads (in the next election) to reduction in the points that A gives to B. (Negative bias may not be that relevant.) This Eurovision Song Contest vote is a Borda like election, but this approach would work as well and better also for Range like elections. One could rig it for ranked elections too (e.g. in a pairwise comparison table based Condorcet method one vote could add only 1/k votes in the some comparison table entry). Would this approach maybe be useful and practical somewhere? What other approaches there are to eliminate this kind of systematical bias? Juho P.S. The highest factors that had lasted systematically for several years were somewhat above 10. I.e. some countries gave systematically 10 times as many points to some other countries than others did. (Since countries participating in the competition and countries that make it to the final are not always the same, the results can not be computed for all country pairs for every year. Therefore I required some minimum number of entries (possibility of A giving points to B) (e.g. 3 or 4) to count the factor for some pair of countries.) Election-Methods mailing list - see http://electorama.com/em for list info
