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There are many ways to tally voting, one such scheme is Instant Runoff Voting where you are allowed to choose your top 3 favorites. However, this scheme can lead to mediocre choices when applied to Academy Award movie wins:
Hi jedishrfu:jedishrfu said:There are many ways to tally voting, one such scheme is Instant Runoff Voting where you are allowed to choose your top 3 favorites. However, this scheme can lead to mediocre choices when applied to Academy Award movie wins:
Hi jedishrfu:jedishrfu said:I quoting the view in the video where "safe" movies win over edgier movies.
Hi mfb:mfb said:You can find counterexamples for that as well.
mfb said:Consider the French election as real life example how it could have gone wrong (lead to a candidate the majority hates).
Hi mfb:mfb said:There were two different right-wing candidates, one moderate candidate and one left-wing candidate, all with roughly similar poll results. The moderate candidate was the only one many would have preferred over other candidates, but he could have gotten kicked out in the first round. He stayed in, and won the second round with a clear victory over one of the right-wing candidates.
Buzz Bloom said:The ordinary runoff the of election the French used is generally an improvement of no runoff, since a no runoff election, which is used in the US, frequently results in a minority winner, while the ordinary runoff more rarely does so.
Hi Stone:StoneTemplePython said:This seems to be going off topic, and is wrong. In the US if no candidate has a majority of electoral college votes, then congress votes in the next president.
There is a process in the works whereby the electoral college may someday become irrelevant.StoneTemplePython said:The issue that I tried to highlight is that you cannot have a minority winner in the US by construction. (The fact that it is done via electoral college and not popular vote further muddies the waters and makes the comparison inappropriate in my view.)
Buzz Bloom said:Hi Stone:
I have to agree that much of this thread has been about voting methods rather than just as applied to the Oscar awards. Perhaps this discussion should be moved to a separate thread.
Regarding the point in the quote above:
(1) There are other US elections than president. For example, governor or senator, or congressman.
(2) Voters in the US do not directly vote to elect the president. They vote for a slate of electors. It is only when the chosen electors do not have a majority vote for a presidential candidate that the house of representatives gets into the process.
Buzz Bloom said:There is a process in the works whereby the electoral college may someday become irrelevant.
https://en.wikipedia.org/wiki/National_Popular_Vote_Interstate_Compact
Hi Stone:StoneTemplePython said:I happen to really like Arrow's Impossibility Theorem but I've only read a bit about it and that was some time ago
Buzz Bloom said:In short, the theorem states that no rank-order electoral system can be designed that always satisfies these three "fairness" criteria:The purpose of most elections is to choose one person as a winner who becomes the elected person. It is NOT to determine an ordering of candidates, but just one single candidate. (There are some elections intended to choose several winners, but that topic should be discussed separately.) I confess that I do not understand what (2) and (3) mean.
1) If every voter prefers alternative X over alternative Y, then the group prefers X over Y.The purpose of eleciong someone
2) If every voter's preference between X and Y remains unchanged, then the group's preference between X and Y will also remain unchanged (even if voters' preferences between other pairs like X and Z, Y and Z, or Z and W change).
3) There is no "dictator": no single voter possesses the power to always determine the group's preference.
Hi stone.StoneTemplePython said:There's a nice little writeup from Terence Tao, here:
The theorem applies to the case of finding a single winner.Buzz Bloom said:The purpose of most elections is to choose one person as a winner who becomes the elected person. It is NOT to determine an ordering of candidates, but just one single candidate.
This is exactly what condition 2 of the theorem states. Adding or removing another candidate should not change the winner (unless the new candidate wins).Buzz Bloom said:@mfb has by examples demonstrated that this method can sometimes choose someone who would not be chosen if a candidate removed him/her self from consideration before the voting takes place, but after the ballots had been prepared. In that case it is assumed this candidate would be removed from the acceptable choices made by voters. (Note that dealing with this case is not a required criterion related to Arrow's theorem.)
Hi mfb:mfb said:The theorem applies to the case of finding a single winner.
It is a hypothetical change (we require that it doesn't happen: If you prefer X over Y, then you should do this no matter which other candidates exist).Buzz Bloom said:I confess I do not understand what "If every voter's preference between X and Y remains unchanged," means. In order to understand this I think I need to understand what it means for a voter to change one or more of his/her preferences. Is this intended to mean a hypothetical change? I just don't get it.
Yes.Buzz Bloom said:Is this intended to mean the same thing as Axiom 2?
Should be fine here. I wonder how you choose voter preferences.Buzz Bloom said:I would also much appreciate your giving me some advice about the Monte-Carlo trials I am working on. I am making progress and nearing a point when I expect to be able to (under some assumptions about the distribution of random numbers) estimate the probability that an outcome like the one in your example would occur. If I understand correctly about the rules of the PF, I am not allowed to discuss the result of this personal project in a thread. However, would it be OK for me to discuss this in an inbox conversation? Would you be interested?
Buzz Bloom said:The current version of my IRV Monte-Carlo tool is a spreadsheet which calculates results for just one trial, and it is limited to one particuar set of assumptions (see below). I next plan to extend it to simultaneous run a large number of trials. For the present I hit F9 to run a new trial and manually keep track of the results.
Hi Stone:StoneTemplePython said:If you do choose to stick with spreadsheets, I'm inferring Excel.