Placeholder Image

字幕列表 影片播放

已審核 字幕已審核
  • '"I never voted for anybody. I always voted against." - W.C. Fields, quoted in "W.C. Fields: His Follies and Fortunes"'.

    「我從不投票給任何人。我總是投反對票。」- W.C. Fields 在《W.C. Fields:他的愚蠢和財富》中寫道。

  • Imagine we want to build a new space port at one of four recently settled Martian bases, and are holding a vote to determine its location.


  • Of the hundred colonists on Mars, 42 live on West Base, 26 on North Base, 15 on South Base, and 17 on East Base.

    在火星上的 100 名殖民地居民中,有 42 位住在西基地、26 位住在北基地、15 位住在南基地,17 位則是住在東基地。

  • For our purposes, let's assume that everyone prefers the space port to be as close to their base as possible, and will vote accordingly.


  • What is the fairest way to conduct that vote?


  • The most straightforward solution would be to just let each individual cast a single ballot, and choose the location with the most votes.


  • This is known as plurality voting, or "first past the post."


  • In this case, West Base wins easily, since it has more residents than any other.


  • And yet, most colonists would consider this the worst result, given how far it is from everyone else.


  • So, is plurality vote really the fairest method?


  • What if we tried a system like instant runoff voting, which accounts for the full range of people's preferences rather than just their top choices?


  • Here's how it would work.


  • First, voters rank each of the options from 1 to 4, and we compare their top picks.

    首先,投票者將所有選項從第 1 名排至第 4 名,我們再來比較他們的首選票數。

  • South receives the fewest votes for first place, so it's eliminated.


  • Its 15 votes get allocated to those voters' second choiceEast Basegiving it a total of 32.

    投給南基地的這 15 票就會被重新分配到那些投票者的第二選擇 — 東基地 — 讓它的總得票數變成 32 票。

  • We then compare top preferences and cut the last place option again.


  • This time, North Base is eliminated.


  • Its residents' second choice would've been South Base, but since that's already gone, the votes go to their third choice.


  • That gives East 58 votes over West's 42, making it the winner.

    於是,東基地總共有 58 票,超過西基地的 42 票,導致東基地勝出。

  • But this doesn't seem fair either.


  • Not only did East start out in second-to-last place, but a majority ranked it among their two least preferred options.


  • Instead of using rankings, we could try voting in multiple rounds, with the top two winners proceeding to a separate runoff.


  • Normally, this would mean West and North winning the first round, and North winning the second.


  • But the residents of East Base realize that while they don't have the votes to win, they can still skew the results in their favor.


  • In the first round, they vote for South Base instead of their own, successfully keeping North from advancing.


  • Thanks to this "tactical voting" by East Base residents, South wins the second round easily, despite being the least populated.


  • Can a system be called fair and good if it incentivizes lying about your preferences?


  • Maybe what we need to do is let voters express a preference in every possible head-to-head matchup.


  • This is known as the Condorcet method.

    這就是孔多塞制 (雙序制)。

  • Consider one matchup: West versus North.


  • All 100 colonists vote on their preference between the two.

    (火星上的) 100 位殖民地居民都要在兩者間選出他們的偏好。

  • So that's West's 42 versus the 58 from North, South, and East, who would all prefer North.

    結果是,西基地的 42 票對北基地的 58 票,因為北、南、東基地的居民都偏好北基地。

  • Now do the same for the other five matchups.


  • The victor will be whichever base wins the most times.


  • Here, North wins three and South wins two.


  • These are indeed the two most central locations, and North has the advantage of not being anyone's least preferred choice.


  • So, does that make the Condorcet method an ideal voting system in general?


  • Not necessarily.


  • Consider an election with three candidates.


  • If voters prefer A over B, and B over C, but prefer C over A, this method fails to select a winner.

    如果投票者喜歡 A 勝過 B,喜歡 B 勝過 C,但喜歡 C 勝過 A,這個方法就選不出贏家。

  • Over the decades, researchers and statisticians have come up with dozens of intricate ways of conducting and counting votes, and some have even been put into practice.


  • But whichever one you choose, it's possible to imagine it delivering an unfair result.


  • It turns out that our intuitive concept of fairness actually contains a number of assumptions that may contradict each other.


  • It doesn't seem fair for some voters to have more influence than others.


  • But nor does it seem fair to simply ignore minority preferences, or encourage people to game the system.


  • In fact, mathematical proofs have shown that for any election with more than two options, it's impossible to design a voting system that doesn't violate at least some theoretically desirable criteria.


  • So while we often think of democracy as a simple matter of counting votes, it's also worth considering who benefits from the different ways of counting them.


  • The United States' use of the electoral college to elect presidents instead of the popular vote has become increasingly contentious in recent years.


  • How exactly does this system work?


  • And is it fair? Or antiquated.


  • Find out here.


'"I never voted for anybody. I always voted against." - W.C. Fields, quoted in "W.C. Fields: His Follies and Fortunes"'.

「我從不投票給任何人。我總是投反對票。」- W.C. Fields 在《W.C. Fields:他的愚蠢和財富》中寫道。

已審核 字幕已審核

影片操作 你可以在這邊進行「影片」的調整,以及「字幕」的顯示

B1 中級 中文 美國腔 TED-Ed 基地 制度 居民 公平 選項

【TED-Ed】 哪種投票制度最好? (Which Voting System Is The Best? - Alex Gendler)

  • 3456 166
    Celine Chien   發佈於 2020 年 09 月 15 日