數學上更優越的投票系統：英語精讀講義

Queen Lion of the Animal Kingdom is displeased.

動物王國的獅子女王很不高興。

She recently introduced elections for the office of king using the first-past-the-post voting system. 文化背景

她最近為了選出國王，引入了領先者當選制的選舉系統。

While her realm started out as a healthy democracy 片語動詞

雖然她的王國一開始是個健康的民主國家，

with many parties running candidates for king,

有許多政黨派出候選人競選國王，

it quickly devolved into two-party rule 用詞

但很快就退化成了兩黨制，

with the citizens not liking either one,

公民們兩個都不喜歡，

but trapped within the system because of a problem called the spoiler effect. 講解

卻因為一個叫「攪局效應」的問題而被困在這個系統中。

However,

然而，

one of Queen Lion's subjects from a distant land,

獅子女王的一位來自遠方的臣民，

Wallaby, has a solution,

小袋鼠，提出了一個解決方案：

the alternative vote. 文化背景

選擇投票制。

What's the difference?

這有什麼區別呢？

To find out, 表達脈絡

為了弄清楚，

let's follow one voter on election day,

讓我們在選舉日跟隨一位選民，

Red Squirrel, under both systems.

也就是紅松鼠，看看他在兩種制度下的表現。

There are five candidates running for king, 用詞

有五位候選人競選國王，

two members of the big parties,

兩名是大黨的成員：

Gorilla and Leopard,

大猩猩和豹子，

and three other candidates,

另外三名是其他候選人：

Turtle, Owl, and Tiger.

海龜、貓頭鷹和老虎。

Under first-past-the-post,

在領先者當選制下，

Red Squirrel gets a ballot where he picks just one candidate.

紅松鼠拿到一張選票，只能從中選擇一位候選人。

Red Squirrel really likes Turtle and even campaigned for him.

紅松鼠非常喜歡海龜，甚至還為他拉過票。

However,

然而，

he knows that his new neighbor, Grey Squirrel,

他知道他的新鄰居灰松鼠

is voting Gorilla.

會把票投給大猩猩。

And what, starts to wonder Red Squirrel,

那麼，紅松鼠開始琢磨，

about all the other animals?

其他的動物呢？

Who are they going to vote for?

他們會投票給誰呢？

The debates on the Animal News Network only had the big parties,

動物新聞網的辯論只有大黨參與，

so Red Squirrel thinks it's going to be a close race between Gorilla and Leopard. 片語搭配

所以紅松鼠認為這將會是大猩猩和豹子之間的激烈競爭。

While he's indifferent toward Gorilla,

雖然他對大猩猩無感，

he's deathly afraid of Leopard. 片語搭配

但他非常害怕豹子。

Because he can only pick a single candidate,

因為只能選一位候選人，

he gives his one vote to Gorilla in hopes of preventing Leopard from becoming king. 講解

他把這唯一的一票投給了大猩猩，希望能阻止豹子成為國王。

This is strategic voting, 文化背景

這就是策略性投票，

and it's a necessity under first-past-the-post.

在領先者當選制下這是不可避免的。

But now let's look at the alternative vote,

但現在我們來看看選擇投票制，

which Wallaby explains to Red Squirrel.

這是小袋鼠向紅松鼠解釋過的。

Instead of picking one and only one candidate, 文法

與其只能選擇一位候選人，

he can rank them in order of his most favorite to his least. 片語搭配

他可以按從最喜歡到最不喜歡的順序給他們排名。

He goes into the voting booth and gets the same ballot as before,

他走進投票亭，拿到了和之前一樣的選票，

but now puts Turtle as his first choice,

但現在把海龜作為他的第一選擇，

Owl as his second,

貓頭鷹作為第二選擇，

and Gorilla as his third.

大猩猩作為第三選擇。

He dislikes Leopard and Tiger equally,

他一樣不喜歡豹子和老虎，

so he stops filling in his ballot and drops it in the box. 片語動詞

所以他不再往下填，並把選票投進了票箱。

At this point,

在這種情況下，

Red Squirrel doesn't care exactly what happens.

紅松鼠並不十分關心接下來會發生什麼。

He has other things on his mind and he heads off. 講解

他心裡有別的事，於是就離開了。

But you, dear citizen, 表達脈絡

但是你，親愛的公民，

want to know how the votes are counted,

想知道選票是如何計算的，

so here goes. 片語搭配

所以開始了。

Turtle, beloved though he is with some of the citizenry, 文法

海龜雖然深受一些公民的喜愛，

comes in last place with only 5%,

但以僅5%的得票率墊底，

and he's eliminated from the race.

被淘汰出局。

Because the voters ranked their candidates in order,

因為選民們對候選人進行了排序，

we can know what would have happened if Turtle didn't run. 文法

我們就能知道如果海龜沒有參選會發生什麼。

Without Turtle, voters like Red Squirrel would have picked Owl instead,

如果沒有海龜，像紅松鼠這樣的選民會轉而選擇貓頭鷹，

so their votes are transferred to her as though Turtle was never in the race at all. 文法

所以他們的選票會轉移給貓頭鷹，就當海龜根本沒有參選過一樣。

This is why the alternative vote is sometimes called instant runoff voting. 文化背景

這就是為什麼選擇投票制有時被稱為「即時排序投票制」。

It's able to simulate a bunch of elections 用詞

它能夠模擬多場選舉，

where the least popular candidate is eliminated after each round

每輪淘汰得票最少的候選人，

without all the time and expense it would take to run a bunch of campaigns one after another.

而無需投入大量時間和金錢接連舉辦一場又一場的競選。

The alternative vote method keeps eliminating the least popular candidate 文法

選擇投票制會不斷淘汰得票最少的候選人，

until someone either wins a majority or only one is left. 文法

直到有人贏得多數票或只剩下最後一人。

As no one has a majority yet,

由於還沒有人獲得多數票，

the next lowest candidate, Tiger, is eliminated.

得票倒數第二的候選人——老虎，被淘汰了。

Tiger voters listed Leopard as their second choice,

投給老虎的選民把豹子列為第二選擇，

so she gets Tiger's votes.

所以老虎的選票就歸她了。

In the last round, Gorilla is eliminated.

在最後一輪，大猩猩被淘汰了。

Gorilla voters listed Owl as their second choice,

投給大猩猩的選民把貓頭鷹列為第二選擇，

so Owl gets those votes,

所以貓頭鷹獲得了這些選票，

wins a majority,

贏得多數票，

and is crowned king.

加冕為王。

The alternative vote is a better system

選擇投票制是一個更好的系統，

because it produces winners that a larger number of voters can agree on. 片語搭配

因為它能選出更多選民都能接受的贏家。

While the alternative vote does have its flaws, 文法

雖然選擇投票制確實也有缺陷，

it's important to note that any problem AV has, 表達脈絡

但重要的是要注意，選擇投票制的任何問題，

first-past-the-post also shares.

領先者當選制同樣也有。

They're both susceptible to gerrymandering, 文化背景

它們都容易受到傑利蠑螈（不當劃分選區）的影響，

they aren't proportional systems,

它們都不是比例代表制，

they can't guarantee a Condorcet winner, 文化背景

它們都不能保證選出孔多塞贏家

which math geeks hate,

（數學極客們對此深惡痛絕，

but there isn't time to explain here,

但這裡沒時間解釋了），

and over time they both trend towards two parties. 片語搭配

而且隨著時間的推移，它們都會趨向於兩黨制。

That being said, 表達脈絡

話雖如此，

alternative vote has a huge advantage that first-past-the-post lacks and makes it mathematically superior,

選擇投票制有一個領先者當選制所缺乏的巨大優勢，使其在數學上更勝一籌：

no spoiler effect.

那就是沒有攪局效應。

Imagine one final election.

想像最後一次選舉。

Two big candidates are running,

兩大候選人參選，

Gorilla and Leopard,

大猩猩和豹子，

and Leopard looks set to win 55 to 45, 片語搭配

豹子眼看要以55對45獲勝，

but then a third-party candidate, Tiger, enters. 文化背景

但這時第三黨候選人老虎加入了。

Tiger manages to convince 15% of the Leopard voters to back him instead. 講解

老虎成功說服了15%原本支持豹子的選民轉而支持他。

Under first-past-the-post,

在領先者當選制下，

Gorilla now wins even though a majority of the voters didn't want him. 文法

儘管大多數選民並不想要大猩猩，他現在卻贏了。

Under the alternative vote,

在選擇投票制下，

because all Tiger voters put Leopard as a second choice,

因為所有投給老虎的選民都會把豹子作為第二選擇，

Leopard still wins

豹子依然會贏，

because a majority of the citizens of the Animal Kingdom would rather have her in charge than Gorilla. 講解

因為動物王國的大多數公民更希望由她而不是大猩猩來掌權。

Using the alternative vote,

使用選擇投票制，

citizens can help support and grow smaller parties that they agree with 片語搭配

公民們可以幫助支持並壯大他們認同的小黨派，

without worrying that they'll put someone they don't like into office. 講解

而不必擔心這會讓一個他們不喜歡的人上台。

After examining the differences between them, 文法

在考察了這兩種制度的區別之後，

Queen Lion decrees that the alternative vote is to be the rule of the land for electing the king 講解

獅子女王頒布法令，下令以選擇投票制作為選出國王的最高法則，

and everyone is happier.

每個人都變得更加快樂了。

Well, 表達脈絡

好吧，

almost everyone.

幾乎每個人。

The two big parties can't be as complacent as they used to be 文法

兩大黨不能再像過去那樣自滿了，

and need to campaign much harder to convince their voters to support them.

並且需要更加努力地拉票，以說服選民支持他們。

This has been the alternative vote explained by me,

以上就是我對選擇投票制的解釋，

CGP Grey.

我是 CGP Grey。

Thank you very much for watching.

非常感謝你的觀看。