TED2010
Esther Duflo: Social experiments to fight poverty
居芙洛：試圖為對抗貧窮，實驗出不同的路
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消弭貧窮不應只憑猜測，援助效果缺乏數據佐證，也不禁讓人質疑其有效性。Clark Medal 經濟學獎得主居芙洛，深入剖析為何各界千方百計想幫助窮人脫離貧困，卻總難如願以償，並試圖為對抗貧窮找出不同的路
Esther Duflo - Development economist
Esther Duflo takes economics out of the lab and into the field to discover the causes of poverty and means to eradicate it. Full bio
Esther Duflo takes economics out of the lab and into the field to discover the causes of poverty and means to eradicate it. Full bio
Double-click the English transcript below to play the video.
00:18
So here it is. You can check: I am short, I'm French,
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各位，看到了嗎？我個子矮小，是個法國人
00:20
I have a pretty strong French accent,
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加上一口非常重的法國口音
00:22
so that's going to be clear in a moment.
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很容易就能看出來吧！
00:26
Maybe a sobering thought
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很怵目驚心吧！
00:28
and something you all know about.
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有些事你們早就知道
00:30
And I suspect many of you gave
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而且我相信你們之中有很多人
00:32
something to the people of Haiti this year.
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今年度捐了些東西給海地
00:35
And there is something else
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還有
00:37
I believe in the back of your mind
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我相信，在內心深處
00:39
you also know.
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你們也都知道
00:41
That is, every day,
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那就是每天
00:43
25,000 children die
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有25,000名孩童不幸喪生
00:45
of entirely preventable causes.
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而且死於完全可事先預防的原因
00:48
That's a Haiti earthquake every eight days.
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這數字相當於每8天就發生一次海地地震
00:51
And I suspect many of you probably gave something
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同樣地，我相信你們之中有很多人
00:53
towards that problem as well,
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也想對這不幸貢獻心力
00:55
but somehow it doesn't happen
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但災難發生的強度
00:57
with the same intensity.
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和帶給人的震撼通常不成正比
00:59
So why is that?
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為什麼呢？
01:02
Well, here is a thought experiment for you.
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看一下這樣一個實驗
01:05
Imagine you have a few million dollars that you've raised --
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假設你募得幾百萬美金
01:07
maybe you're a politician in a developing country
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你是個開發中國家的官員
01:10
and you have a budget to spend. You want to spend it on the poor:
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為了幫助窮人，編列了相關預算
01:13
How do you go about it?
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你會從何著手呢?
01:16
Do you believe the people who tell you
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是相信你所聽到的
01:18
that all we need to do is to spend money?
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只要花錢
01:20
That we know how to eradicate poverty,
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就能幫助窮人脫離貧窮
01:23
we just need to do more?
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現在只是做得還不夠？
01:25
Or do you believe the people who tell you that
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或是相信另外一種說法
01:27
aid is not going to help, on the contrary it might hurt,
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援助根本無法解決問題，相反地，還會造成傷害
01:30
it might exacerbate corruption, dependence, etc.?
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像是助長貪污及依賴
01:34
Or maybe you turn to the past.
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回顧過去
01:36
After all, we have spent billions of dollars on aid.
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已有幾十億美金花在援助上
01:39
Maybe you look at the past and see.
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或許你會想知道
01:41
Has it done any good?
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這些援助究竟有沒有用？
01:43
And, sadly, we don't know.
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很遺撼，我們不知道
01:45
And worst of all, we will never know.
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更糟的是，我們永遠不會知道
01:49
And the reason is that -- take Africa for example.
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為什麼會這樣呢？舉非洲的例子
01:51
Africans have already got a lot of aid.
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非洲人得到很多援助
01:53
These are the blue bars.
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看看這些藍色長條圖
01:55
And the GDP in Africa is not making much progress.
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然而非洲的GDP始終沒有任何改善
01:58
Okay, fine. How do you know what
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那又怎樣？你怎麼知道
02:00
would have happened without the aid?
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如果沒有援助又會是怎樣呢？
02:02
Maybe it would have been much worse,
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也許GDP比現在更糟
02:05
or maybe it would have been better.
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或是更好也不一定
02:07
We have no idea. We don't know what the counterfactual is.
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我們不知道，我們無法知道這不存在的事實
02:10
There's only one Africa.
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只有一個非洲無從驗證起
02:12
So what do you do?
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那該怎麼辦呢？
02:14
To give the aid, and hope and pray that something comes out of it?
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繼續給予援助，滿懷希望地祈禱著問題能夠解決？
02:18
Or do you focus on your everyday life
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或是繼續過日子
02:21
and let the earthquake every eight days
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無視於每8天
02:23
continue to happen?
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持續發生的地震?
02:25
The thing is, if we don't know
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事實上，如果我們不知道
02:27
whether we are doing any good,
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自己所做的事是對的
02:29
we are not any better
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我們甚至不如
02:31
than the Medieval doctors and their leeches.
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中世紀的醫生和那些水蛭
02:34
Sometimes the patient gets better, sometimes the patient dies.
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有時病人的病好轉了，有時卻回天乏術
02:37
Is it the leeches? Is it something else?
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到底是因為水蛭或是其他原因？
02:40
We don't know.
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誰知道
02:42
So here are some other questions.
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在這我提出幾個問題
02:44
They're smaller questions,
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只是小問題
02:46
but they are not that small.
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但並非全然不重要
02:48
Immunization, that's the cheapest way
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疫苗接種，現今最便宜的方法
02:51
to save a child's life.
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拯救孩童寶貴的生命
02:53
And the world has spent a lot of money on it:
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我們也已為此花費龐大金錢
02:55
The GAVI and the Gates Foundations
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全球疫苗免疫聯盟和比爾蓋茲基金會
02:57
are each pledging a lot of money towards it,
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也分別砸下很多的資源
02:59
and developing countries themselves have been doing a lot of effort.
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開發中國家自身也投入相當多的心力
03:02
And yet, every year
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然而，毎年
03:04
at least 25 million children
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至少2500萬名孩童
03:06
do not get the immunization they should get.
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卻得不到應該接種的疫苗
03:09
So this is what you call a "last mile problem."
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這就是所謂的"最後一哩難題"
03:12
The technology is there,
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明明技術已經純熟
03:14
the infrastructure is there,
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基礎設施也有
03:16
and yet it doesn't happen.
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結果卻仍不如預期
03:18
So you have your million.
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所以縱使資金充裕
03:20
How do you use your million
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問題是你該怎麼使用
03:22
to solve this last mile problem?
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才能解決這最後一哩的難題
03:24
And here's another question:
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還有個問題
03:26
Malaria. Malaria kills almost
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瘧疾，瘧疾每年至少奪走
03:29
900,000 people every year,
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90萬條人命
03:32
most of them in Sub-Saharan Africa,
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大部份都發生在撒哈拉以南非洲
03:34
most of them under five.
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而且是5歲以下孩童
03:36
In fact, that is the leading cause of under-five mortality.
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事實上這也是造成5歲以下孩童死亡的首要原因
03:39
We already know how to kill malaria,
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我們早就知道對抗瘧疾的方法
03:42
but some people come to you and say,
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但有人跑來告訴你
03:44
"You have your millions. How about bed nets?"
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你有那麼多錢，拿來買蚊帳如何？
03:47
Bed nets are very cheap.
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蚊帳很便宜
03:49
For 10 dollars, you can manufacture and ship
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10塊錢，包含製造加運送
03:52
an insecticide treated bed net
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還加防蟲劑處理過
03:54
and you can teach someone to use them.
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你可以教導當地居民如何使用
03:56
And, not only do they protect the people who sleep under them,
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這樣，不只睡在蚊帳內的人得到保護
03:59
but they have these great contagion benefits.
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還能產生連鎖效應
04:01
If half of a community sleeps under a net,
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如果一半居民使用蚊帳
04:04
the other half also benefits
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另一半人跟著受惠
04:06
because the contagion of the disease spread.
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就是因為防疫效果的擴散
04:09
And yet, only a quarter of kids at risk sleep under a net.
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然而，瘧疾高危險群的孩童僅有1/4睡在蚊帳內
04:12
Societies should be willing to go out
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很多人應該會願意
04:14
and subsidize the net, give them for free,
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免費捐贈蚊帳
04:16
or, for that matter, pay people to use them
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或是，提供補貼
04:18
because of those contagion benefits.
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因為這樣，防疫效果會更好
04:20
"Not so fast," say other people.
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有些人則認為，太快了吧
04:22
"If you give the nets for free,
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如果你免費送蚊帳
04:24
people are not going to value them.
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他們不會珍惜
04:26
They're not going to use them,
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也不會好好用
04:28
or at least they're not going to use them as bed nets,
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也許拿去做別的用途
04:30
maybe as fishing nets."
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被當成魚網也說不定
04:32
So, what do you do?
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所以你該如何做呢？
04:34
Do you give the nets for free to maximize coverage,
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免費送，擴大防疫效果
04:36
or do you make people pay
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或是他們必須付點錢
04:38
in order to make sure that they really value them?
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確保他們會善加利用？
04:40
How do you know?
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你又怎麼知道結果呢？
04:42
And a third question: Education.
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第三個問題：教育
04:44
Maybe that's the solution, maybe we should send kids to school.
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也許這是個方法，讓孩童接受教育
04:46
But how do you do that?
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但該怎麼做呢？
04:48
Do you hire teachers? Do you build more schools?
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聘請老師？加蓋學校？
04:50
Do you provide school lunch?
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要不要供應午餐？
04:52
How do you know?
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你又怎麼知道那種方法更好？
04:54
So here is the thing.
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這就是問題所在
04:56
I cannot answer the big question,
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我也不知道
04:58
whether aid did any good or not.
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援助究竟是好是壞
05:00
But these three questions, I can answer them.
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但以下這三個問題，我可以回答
05:04
It's not the Middle Ages anymore,
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現在不是中世紀
05:06
it's the 21st century.
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現在是21世紀
05:08
And in the 20th century,
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20世紀時
05:10
randomized, controlled trials
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隨機對照試驗
05:12
have revolutionized medicine
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引發醫藥革命
05:14
by allowing us to distinguish
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也讓我們有能力區分
05:16
between drugs that work
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這些藥
05:18
and drugs that don't work.
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究竟有沒有效果
05:20
And you can do the same
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現在你可以用同樣的方法
05:22
randomized, controlled trial for social policy.
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把隨機對照試驗用在社會政策上
05:25
You can put social innovation to the same
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你可以在社會政策上，進行相同的
05:27
rigorous, scientific tests
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嚴謹的科學測試
05:29
that we use for drugs.
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如同我們對藥物一般
05:31
And in this way, you can take the guesswork
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減少用猜測的方式
05:34
out of policy-making
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來制定政策
05:36
by knowing what works,
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而是清楚知道那些政策可行
05:38
what doesn't work and why.
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那些不可行，還有原因是什麼
05:40
And I'll give you some examples with those three questions.
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再舉幾個例子
05:44
So I start with immunization.
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就從疫苗開始
05:46
Here's Udaipur District, Rajasthan. Beautiful.
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這裡是印度的拉賈斯坦烏代布爾區，很美吧
05:49
Well, when I started working there,
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當我開始在那工作時
05:51
about one percent of children
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只有百分之一的孩童
05:53
were fully immunized.
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對麻疹有免疫
05:55
That's bad, but there are places like that.
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很糟的數字，但很多地方都是這樣
05:58
Now, it's not because the vaccines are not there --
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原因並非因為沒有疫苗
06:00
they are there and they are free --
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不但有，而且免費
06:02
and it's not because parents do not care about their kids.
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也並非父母親不關心自己的小孩
06:05
The same child that is not immunized against measles,
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沒有免疫的小孩
06:08
if they do get measles, parents will spend
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如果真得了麻疹，父母親會花
06:10
thousands of rupees to help them.
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大把鈔票來救自己的孩子
06:12
So you get these empty village subcenters
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所以，如你所看到的，疫苗注射中心是空的
06:14
and crowded hospitals.
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醫院卻擠滿了人
06:16
So what is the problem?
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這問題到底在哪？
06:18
Well, part of the problem, surely, is people do not fully understand.
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部份原因，當然，是當地居民對麻疹並不了解
06:21
After all, in this country as well,
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畢竟，在這偏僻地方
06:23
all sorts of myths and misconceptions
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對於麻疹
06:25
go around immunization.
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充滿謎團和誤解
06:28
So if that's the case, that's difficult,
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如果真是這樣，很糟糕
06:30
because persuasion is really difficult.
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因為人很難被說服
06:33
But maybe there is another problem as well.
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即使讓他們接受了，到實際付諸行動
06:35
It's going from intention to action.
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中間還是會發生很多問題
06:38
Imagine you are a mother
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假設你是個母親
06:40
in Udaipur District, Rajasthan.
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在拉賈斯坦烏代布爾區這樣一個偏遠地方
06:42
You have to walk a few kilometers to get your kids immunized.
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為了讓孩子接種疫苗，首先必須走好幾公里的路
06:45
And maybe when you get there, what you find is this:
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好不容易走到了，在你眼前的卻是
06:47
The subcenter is closed. Ao you have to come back,
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關了門的注射中心，你只好打道回府
06:49
and you are so busy and you have so many other things to do,
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但你真的很忙，有太多其他的事要做了
06:52
you will always tend to postpone and postpone,
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你只好一直拖著...拖著
06:54
and eventually it gets too late.
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直到一切都太遲了
06:56
Well, if that's the problem, then that's much easier.
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好吧，如果問題如此，還好解決
06:59
Because A, we can make it easy,
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因為第一，想辦法讓它簡單些
07:02
and B, we can maybe
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第二，我們可以
07:04
give people a reason to act today,
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給個立即採取行動的誘因
07:06
rather than wait till tomorrow.
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而不是拖到明天
07:08
So these are simple ideas, but we didn't know.
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就這麼簡單的想法，但不知可不可行
07:10
So let's try them.
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所以試試看囉
07:12
So what we did is we did a randomized, controlled trial
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怎麼做呢?用隨機對照試驗
07:15
in 134 villages in Udaipur Districts.
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在烏代布爾區的134個村落
07:17
So the blue dots
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這些藍色的點
07:19
are selected randomly.
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都是隨機挑選的
07:21
We made it easy -- I'll tell you how in a moment.
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方法很簡單，待會你就知道
07:24
In the red dots, we made it easy
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這些紅點，也很簡單
07:26
and gave people a reason to act now.
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給個激勵，誘使他們付諸行動
07:28
The white dots are comparisons, nothing changed.
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白色的點是參考值，不加任何變數
07:31
So we make it easy by organizing
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重新整理
07:33
this monthly camp where people can
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每個月的營地
07:35
get their kids immunized.
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這裡是人們可以孩童接種疫苗的地方
07:37
And then you make it easy
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加上簡單的方法
07:39
and give a reason to act now
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給他們付諸行動的理由
07:41
by adding a kilo of lentils for each immunization.
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例如每接種一次，就給一公斤的扁豆
07:44
Now, a kilo of lentils is tiny.
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一公斤扁豆根本微不足道
07:47
It's never going to convince anybody
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不可能說服得了任何人
07:49
to do something that they don't want to do.
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去做他們不想做的事
07:51
On the other hand, if your problem is you tend to postpone,
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另一方面，如果問題是你想拖延
07:54
then it might give you a reason to act today
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那就給一個理由讓你現在就去做
07:56
rather than later.
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而不是等到以後
07:58
So what do we find?
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那有何發現呢？
08:00
Well, beforehand, everything is the same.
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嗯，一開始，所有事情都一樣
08:02
That's the beauty of randomization.
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這是隨機採樣的好處
08:04
Afterwards,
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然而，之後
08:06
the camp -- just having the camp --
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營地，光是營地
08:08
increases immunization from six percent to 17 percent.
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接種疫苗的比例由6%增加至17%
08:10
That's full immunization.
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這是免疫力數據
08:12
That's not bad, that's a good improvement.
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不錯吧，進步很多
08:14
Add the lentils and you reach to 38 percent.
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加上扁豆後，這比例又增加至38%
08:17
So here you've got your answer.
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所以結論是
08:19
Make it easy and give a kilo of lentils,
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做法很簡單，只要給一公斤的扁豆
08:21
you multiply immunization rate by six.
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免疫力可以提高6倍
08:24
Now, you might say, "Well, but it's not sustainable.
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不過，你也許會說＂這方法無法持續＂
08:26
We cannot keep giving lentils to people."
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"我們不能一直給扁豆"
08:28
Well, it turns out it's wrong economics,
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很顯然，這是錯誤的經濟學
08:30
because it is cheaper
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事實上，比起什麼都沒有
08:32
to give lentils than not to give them.
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給扁豆其實便宜多了
08:34
Since you have to pay for the nurse anyway,
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反正無論如何，這些醫護人員的薪水都得付
08:36
the cost per immunization
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每一注射劑的成本
08:38
ends up being cheaper if you give incentives than if you don't.
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加上扁豆最終還是便宜多了
08:42
How about bed nets?
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那麼蚊帳呢？
08:44
Should you give them for free, or should you ask people to pay for them?
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免費捐贈？還是收費呢？
08:47
So the answer hinges
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這問題的答案
08:49
on the answer to three simple questions.
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和三個簡單的問題有關
08:51
One is: If people must pay for a bed net,
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第一，如果蚊帳要收費
08:54
are they going to purchase them?
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當地居民會買嗎？
08:56
The second one is:
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第二
08:58
If I give bed nets for free,
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如果免費
09:00
are people going to use them?
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他們會用嗎？
09:02
And the third one is:
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第三個問題
09:04
Do free bed nets discourage future purchase?
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習慣免費的蚊帳，以後會不會不願花錢買呢？
09:06
The third one is important
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第三個問題很重要
09:08
because if we think people get used to handouts,
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因為，如果我們認為人們一旦習慣了接受施捨
09:11
it might destroy markets to distribute free bed nets.
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可能會破壞市場機制
09:14
Now this is a debate that has generated
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這議題已引起爭論
09:16
a lot of emotion and angry rhetoric.
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很多是情緒性，憤怒的言論
09:19
It's more ideological than practical,
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很理想但不切實際
09:21
but it turns out it's an easy question.
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其實只不過是個簡單問題
09:23
We can know the answer to this question.
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只要一個實驗
09:25
We can just run an experiment.
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就可以得到答案
09:27
And many experiments have been run, and they all have the same results,
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而且經由很多實驗，都產生相同的結果
09:29
so I'm just going to talk to you about one.
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我來告訴你們其中一個
09:32
And this one that was in Kenya,
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這個發生在肯亞
09:34
they went around and distributed to people
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他們到每個地方分發給人們
09:36
vouchers, discount vouchers.
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兌換券，折扣券等
09:38
So people with their voucher
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拿著這些兌換券
09:40
could get the bed net in the local pharmacy.
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就可以在當地藥局得到蚊帳
09:42
And some people get 100 percent discount,
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有些券是100%免費兌換
09:45
and some people get 20 percent discounts,
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有些20%折扣
09:47
and some people get 50 percent discount, etc.
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有些則是50%的折扣
09:50
And now we can see what happens.
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現在我們來看看結果
09:52
So, how about the purchasing?
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結果呢？
09:54
Well, what you can see is that
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你可以看到
09:56
when people have to pay for their bed nets,
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當人們必須花錢買蚊帳時
09:58
the coverage rate really falls down a lot.
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買的人真得少很多
10:01
So even with partial subsidy,
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即便給予部份補貼
10:03
three dollars is still not the full cost of a bed net,
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蚊帳總成本絕不只3塊錢
10:06
and now you only have 20 percent of the people with the bed nets,
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因為只剩20%的人有蚊帳
10:08
you lose the health immunity, that's not great.
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失去蚊帳覆蓋率等於失去免疫力，這可不是好事
10:11
Second thing is, how about the use?
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第二件事，他們怎麼用呢？
10:13
Well, the good news is, people, if they have the bed nets,
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好消息是，只要是有蚊帳的人
10:15
will use the bed nets regardless of how they got it.
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都會使用，不管是如何得到的
10:18
If they get it for free, they use it.
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免費得到的也好
10:20
If they have to pay for it, they use it.
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付費的也好
10:22
How about the long term?
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長期來看呢？
10:24
In the long term,
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長期而言
10:26
people who got the free bed nets,
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人們拿到免費的蚊帳
10:28
one year later, were offered the option
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一年以後
10:30
to purchase a bed net at two dollars.
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可以用2元買到新的蚊帳
10:33
And people who got the free one
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而且一開始拿到免費蚊帳的人
10:35
were actually more likely to purchase the second one
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大部份都會去買第二個
10:38
than people who didn't get a free one.
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相較那些沒有拿過免費蚊帳的人
10:40
So people do not get used to handouts; they get used to nets.
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所以人們並沒有習慣接受施捨，他們習慣的是蚊帳
10:43
Maybe we need to give them a little bit more credit.
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也許我們應該更相信他們
10:48
So, that's for bed nets. So you will think, "That's great.
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這是蚊帳的實驗。你一定想說，那太好了
10:50
You know how to immunize kids, you know how to give bed nets."
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現在你知道如何防疫，如何給蚊帳
10:53
But what politicians need is a range of options.
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但政治人物需要的是一連串的選擇
10:56
They need to know: Out of all the things I could do,
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他們要知道，在這些一連串我能做的事中
10:59
what is the best way to achieve my goals?
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什麼是達成目標最好的方法？
11:02
So suppose your goal is to get kids into school.
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所以假設你的目的是讓小孩上學
11:05
There are so many things you could do. You could pay for uniforms,
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太多的事你能做。你可以買制服
11:08
you could eliminate fees, you could build latrines,
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免除學雜費，蓋廁所
11:10
you could give girls sanitary pads, etc., etc.
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你還可以發送女孩衛生棉...等等
11:13
So what's the best?
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但做什麼最好?
11:15
Well, at some level, we think
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嗯，就某種程度來說，我們認為
11:17
all of these things should work.
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所有這些事都該做
11:19
So, is that sufficient? If we think they should work intuitively,
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那麼，做這些就夠嗎？如果這些我們直覺認為都是該做的
11:21
should we go for them?
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就應該直接去做嗎？
11:23
Well, in business, that's certainly not the way we would go about it.
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就事論事，當然不該這麼衝動
11:27
Consider for example
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考慮一種情況
11:29
transporting goods.
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運送物資
11:31
Before the canals were invented
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在運河尚未發明
11:33
in Britain before the Industrial Revolution,
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在英國工業革命以前
11:36
goods used to go on horse carts.
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馬車是主要的運輸工具
11:38
And then canals were built,
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直到運河出現
11:40
and with the same horseman and the same horse,
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相較於馬車
11:43
you could carry ten times as much cargo.
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運輸量比起以前多了10倍
11:46
So should they have continued
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所以是該繼續
11:48
to carry the goods on the horse carts, on the ground,
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用馬車代步，運送貨物
11:51
that they would eventually get there?
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反正這種方式終究也會抵達目的地
11:53
Well, if that had been the case,
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假如是這樣
11:55
there would have been no Industrial Revolution.
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也就不會有英國工業革命了
11:57
So why shouldn't we do the same with social policy?
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所以為何不把革命用在社會政策呢
12:00
In technology, we spend so much time
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對於科技，我們花了如此多的時間
12:02
experimenting, fine-tuning,
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做實驗，做微調
12:04
getting the absolute cheapest way to do something,
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試圖找出最省成本方法來解決事情
12:06
so why aren't we doing that with social policy?
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為什麼不能用在社會政策上呢？
12:09
Well, with experiments, what you can do
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藉由實驗，你可以
12:11
is answer a simple question.
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找到一個簡單問題的答案
12:13
Suppose you have 100 dollars to spend
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假設你有100元的預算
12:15
on various interventions.
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來推行各種措施
12:17
How many extra years of education
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例如增加額外教育年限
12:19
do you get for your hundred dollars?
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準備好你的經費了嗎？
12:21
Now I'm going to show you
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現在讓我來告訴你
12:23
what we get with various education interventions.
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我們是如何干預教育政策的
12:27
So the first ones are if you want the usual suspects,
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一開始你一定會想
12:29
hire teachers, school meals,
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請老師，供應營養午餐
12:31
school uniforms, scholarships.
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提供制服，獎學金
12:33
And that's not bad. For your hundred dollars,
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很好啊！幾百元就能做到
12:35
you get between one and three extra years of education.
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結果你多得了1至3年的額外教育
12:39
Things that don't work so well is bribing parents,
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但父母親可不是這麼好騙的
12:41
just because so many kids are already going to school
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因為已經有很多小孩上學了
12:44
that you end up spending a lot of money.
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結果你只是白花了很多錢
12:46
And here are the most surprising results.
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然而，最讓人訝異的是
12:49
Tell people the benefits of education,
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只要告訴人們受教育的好處
12:52
that's very cheap to do.
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很便宜的方法
12:54
So for every hundred dollars you spend doing that,
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但平均每花一百元用在推廣受教育的好處
12:57
you get 40 extra years of education.
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結果多了40年額外教育
13:00
And, in places where there are worms,
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另外，在那些有寄生蟲的地方
13:02
intestinal worms,
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例如蛔蟲
13:04
cure the kids of their worms.
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只要治好這問題
13:06
And for every hundred dollars,
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每一百元
13:08
you get almost 30 extra years of education.
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可以多將近30年的額外教育
13:11
So this is not your intuition,
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這不是直覺
13:13
this is not what people would have gone for,
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也不是原本想做的事
13:15
and yet, these are the programs that work.
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但卻可以解決問題
13:18
We need that kind of information, we need more of it,
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我們需要這類訊息，更多的訊息
13:20
and then we need to guide policy.
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做為政策依據
13:24
So now, I started from the big problem, and I couldn't answer it.
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回到演講一開始，我提的這個大問題，我還是沒有答案
13:27
And I cut it into smaller questions,
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但我可以把它們分成不同的小問題
13:30
and I have the answer to these smaller questions.
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對於這些小問題，我能回答
13:32
And they are good, scientific, robust answers.
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而且是正確的，科學的，強而有力的答案
13:36
So let's go back to Haiti for a moment.
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先回到海地
13:39
In Haiti, about 200,000 people died --
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海地地震造成20萬人不幸喪生
13:43
actually, a bit more by the latest estimate.
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事實上，根據最新估計，死亡人數還更多些
13:45
And the response of the world was great:
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來自全世界的援助也很可觀
13:47
Two billion dollars got pledged just last month,
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光上個月募集了20億美金
13:51
so that's about 10,000 dollars per death.
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大約是，每一死亡1萬美金
13:53
That doesn't sound like that much when you think about it.
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仔細想想好像也沒多少
13:56
But if we were willing to spend 10,000 dollars
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但如果我們願意將1萬美金
13:59
for every child under five who dies,
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救助五歲以下的孩童，免受死亡威脅
14:02
that would be 90 billion per year
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光就這單一問題
14:05
just for that problem.
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一年就有900億
14:07
And yet it doesn't happen.
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然而這從沒發生過
14:09
So, why is that?
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為什麼呢?
14:11
Well, I think what part of the problem is that,
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我認為部份原因是
14:13
in Haiti, although the problem is huge,
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海地地震，雖然災情慘重
14:15
somehow we understand it, it's localized.
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但受災區集中，很容易估計
14:17
You give your money to Doctors Without Borders,
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你可以捐錢給＂無國界醫生＂
14:19
you give your money to Partners In Health,
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你也可以捐給＂健康伙伴＂
14:21
and they'll send in the doctors, and they'll send in the lumber,
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他們會派醫療團隊，會運送很多建材木料
14:24
and they'll helicopter things out and in.
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甚至派出直升機展開救援行動
14:27
And the problem of poverty is not like that.
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但貧窮這問題完全不是這麼回事
14:29
So, first, it's mostly invisible;
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首先，它可以說是無形的
14:31
second, it's huge;
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再來，範圍廣大
14:33
and third, we don't know whether we are doing the right thing.
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第三，我們根本不知道我們所做所為是對的
14:36
There's no silver bullet.
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目前沒有打擊貧窮的妙方
14:38
You cannot helicopter people out of poverty.
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你不能用直升機把貧窮載走
14:40
And that's very frustrating.
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多麼令人沮喪！
14:42
But look what we just did today.
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但看看我們所做的
14:45
I gave you three simple answers to three questions:
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也許給你們三個簡單的回答
14:48
Give lentils to immunize people,
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送扁豆激勵接種疫苗的人
14:50
provide free bed nets, deworm children.
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提供免費蚊帳，清除孩童體內的蛔蟲
14:52
With immunization or bed nets,
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無論是疫苗或蚊帳
14:54
you can save a life for 300 dollars per life saved.
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300元就足以拯救一條寶貴的生命
14:57
With deworming, you can get
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藉由清除體內蛔蟲
14:59
an extra year of education for three dollars.
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3元就可以增加一年的額外教育
15:02
So we cannot eradicate poverty just yet,
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雖然還是無法擺脫貧窮
15:05
but we can get started.
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但至少我們開始了
15:07
And maybe we can get started small
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也許只是一小步
15:09
with things that we know are effective.
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但我們已掌握很多有效的方法
15:12
Here's an example of how this can be powerful.
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一個例子告訴我們，這些方法可能產生很大的效果
15:14
Deworming.
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清除蛔蟲
15:16
Worms have a little bit of a problem grabbing the headlines.
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蟲子難登大雅之堂
15:18
They are not beautiful and don't kill anybody.
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很醜陋，但還不至於致人於死
15:21
And yet, when the young global leader in Davos
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然而，當＂年輕的全球領導人＂在瑞士達沃斯
15:23
showed the numbers I gave you,
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告訴全世界這些數字時
15:25
they started Deworm the World.
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"世界除蟲組織" 成立了
15:27
And thanks to Deworm the World,
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多虧了這個組織成立
15:29
and the effort of many country governments and foundations,
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也多虧了各國政府及基金會的努力
15:31
20 million school-aged children got dewormed in 2009.
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2009年有2仟萬名學齡孩童得到幫助
15:34
So this evidence is powerful.
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強而有力的證據
15:36
It can prompt action.
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是可以引發具體的行動
15:38
So we should get started now.
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我們應該立即著手進行
15:40
It's not going to be easy.
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這當然不容易
15:42
It's a very slow process.
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過程相當漫長
15:44
You have to keep experimenting, and sometimes ideology
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除了不斷的實驗，有時理想
15:46
has to be trumped by practicality.
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很容易被現實打敗
15:48
And sometimes what works somewhere doesn't work elsewhere.
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有時這方法在這地方成功，換別的地方又不一定
15:51
So it's a slow process,
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很緩慢，很冗長
15:53
but there is no other way.
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卻沒有更好的方法
15:55
These economics I'm proposing,
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我所提出的經濟學理論
15:57
it's like 20th century medicine.
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就像20世紀的醫藥革命
15:59
It's a slow, deliberative process
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得經過漫長，嚴謹的
16:01
of discovery.
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實證發現
16:03
There is no miracle cure,
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沒有神奇藥方
16:05
but modern medicine is saving
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但現代醫藥
16:07
millions of lives every year,
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每年能拯救數百萬條生命
16:09
and we can do the same thing.
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我們可以複製這成功經驗
16:13
And now, maybe, we can go back to the bigger question
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現在，又回到這大問題
16:16
that I started with at the beginning.
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演講一開始我提出的問題
16:19
I cannot tell you
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我還是沒辦法告訴你
16:21
whether the aid we have spent in the past has made a difference,
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過去這些援助究竟有沒有效果
16:24
but can we come back here in 30 years
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但30年後
16:27
and say, "What we have done,
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我們可以說＂我們所做的，
16:30
it really prompted a change for the better."
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真的讓未來變得更好＂
16:33
I believe we can and I hope we will.
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我相信我們可以做到，我希望我們可以做到
16:35
Thank you.
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謝謝大家
16:37
(Applause)
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(掌聲)
ABOUT THE SPEAKER
Esther Duflo - Development economistEsther Duflo takes economics out of the lab and into the field to discover the causes of poverty and means to eradicate it.
Why you should listen
2009 MacArthur fellow Esther Duflo is pushing the field of development economics by studying specific causal relationships that lead to or perpetuate poverty. She looks at close-to-home issues: household behavior, education, access to finance and health.
At MIT, she's the founder and director of the Jameel Poverty Action Lab (J-PAL), a research network that evaluates social programs. It's concerned less with wide-ranging policy than with specific questions. Sample: If schoolkids could get their uniforms for free, would attendance go up? What's an effective way to reward mothers for immunizing their babies? Randomized trials offer new insights toward creating global equity and prosperity. Her work may blur the lines between economics and activism, but it's a role Duflo not only considers comfortable but vital.
Her new book is Poor Economics, with Abhijit W. Banerjee.
Esther Duflo | Speaker | TED.com