TED2010
Esther Duflo: Social experiments to fight poverty
Esther Duflo:战胜贫困的社会实验
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减少贫困与其说是科学，不如说是试验猜测。而缺少援助产生的影响的相关数据，带来到底该怎样提供援助的问题。但是卡拉克奖得主Esther Duflo讨论哪些努力是有帮助哪些可能有害——通过随机化测试的方案。
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 你们可以看到 我很矮 我是法国人
00:20
I have a pretty strong French accent,
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我有很重的法国口音
00:22
so that's going to be clear in a moment.
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一会你们就会发现这一点
00:26
Maybe a sobering thought
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或者这很触目惊心
00:28
and something you all know about.
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你们都知道这些事
00:30
And I suspect many of you gave
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我想你们中的很多人
00:32
something to the people of Haiti this year.
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今年还给海地人捐献了东西
00:35
And there is something else
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但还有些别的事
00:37
I believe in the back of your mind
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我相信在你们脑中
00:39
you also know.
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你们也知道
00:41
That is, every day,
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就是每天都会有
00:43
25,000 children die
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25,000个孩子丧生
00:45
of entirely preventable causes.
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死于完全可以预防的原因
00:48
That's a Haiti earthquake every eight days.
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那是每八天的海地地震情况
00:51
And I suspect many of you probably gave something
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我想你们中的很多人也许
00:53
towards that problem as well,
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也想过这个问题
00:55
but somehow it doesn't happen
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但是
00:57
with the same intensity.
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每次灾难的破坏程度不太一样
00:59
So why is that?
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那么 这是为什么呢？
01:02
Well, here is a thought experiment for you.
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你们看一下这样一个实验
01:05
Imagine you have a few million dollars that you've raised --
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想象下 你募集了几百万美金
01:07
maybe you're a politician in a developing country
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你可能是某个发展中国家的官员
01:10
and you have a budget to spend. You want to spend it on the poor:
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你有个花钱的预算 你想把钱用在帮助贫困上
01:13
How do you go about it?
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你会怎样做？
01:16
Do you believe the people who tell you
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你会相信这样的人：
01:18
that all we need to do is to spend money?
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他们认为 我们所有该做的就是花钱
01:20
That we know how to eradicate poverty,
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我们知道如何消除贫困
01:23
we just need to do more?
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我们只是需要做更多
01:25
Or do you believe the people who tell you that
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还是会相信另外一些人：
01:27
aid is not going to help, on the contrary it might hurt,
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他们认为 援助没啥用，反而有坏处
01:30
it might exacerbate corruption, dependence, etc.?
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它可能助长腐败、依赖性等等
01:34
Or maybe you turn to the past.
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或者你会想想过去
01:36
After all, we have spent billions of dollars on aid.
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毕竟，我们花费了数十亿美金在援助上
01:39
Maybe you look at the past and see.
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你们看看过去
01:41
Has it done any good?
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看看援助是否做了些好事
01:43
And, sadly, we don't know.
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很遗憾，我们不知道
01:45
And worst of all, we will never know.
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最糟糕的是，我们永远也不会知道
01:49
And the reason is that -- take Africa for example.
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而原因是——拿非洲作为例子
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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就是这些蓝条
01:55
And the GDP in Africa is not making much progress.
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而非洲的GDP却没咋增长
01:58
Okay, fine. How do you know what
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好的， 你们如何得知
02:00
would have happened without the aid?
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没有援助会发生什么
02:02
Maybe it would have been much worse,
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或许会坏很多
02:05
or maybe it would have been better.
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或许会好很多
02:07
We have no idea. We don't know what the counterfactual is.
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我们不知道 不知道这样假设会如何
02:10
There's only one Africa.
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只有一个非洲
02:12
So what do you do?
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那么 你们会怎样做
02:14
To give the aid, and hope and pray that something comes out of it?
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给援助 然后希望、祈祷它会带了些好处
02:18
Or do you focus on your everyday life
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还是 仅仅关注自己的每日生活
02:21
and let the earthquake every eight days
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而让每八天一次的地震
02:23
continue to happen?
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继续发生？
02:25
The thing is, if we don't know
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要注意 如果我们不知道
02:27
whether we are doing any good,
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我们是否在做好事
02:29
we are not any better
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我们就甚至还不如
02:31
than the Medieval doctors and their leeches.
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中世纪的医生和那些寄生虫做得更好
02:34
Sometimes the patient gets better, sometimes the patient dies.
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有时候病人治好 有时候病人死去
02:37
Is it the leeches? Is it something else?
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这是因为寄生虫，还是因为别的什么？
02:40
We don't know.
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我们不知道
02:42
So here are some other questions.
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还要另外几个问题
02:44
They're smaller questions,
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这些问题很小
02:46
but they are not that small.
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但又不是那么小
02:48
Immunization, that's the cheapest way
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免疫 这是挽救孩子生命
02:51
to save a child's life.
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最便宜的方法
02:53
And the world has spent a lot of money on it:
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世界花了很多钱在免疫上
02:55
The GAVI and the Gates Foundations
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国际免疫预防联合会（GAVI）和盖茨基金会
02:57
are each pledging a lot of money towards it,
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都在免疫上投入很多钱
02:59
and developing countries themselves have been doing a lot of effort.
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发展国家自身也做了很多努力
03:02
And yet, every year
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然而，每年
03:04
at least 25 million children
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至少2500万儿童
03:06
do not get the immunization they should get.
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不能得到他们本应得到的免疫
03:09
So this is what you call a "last mile problem."
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这就是所谓的“最后一英里难题” （last mile problem 指人们能得到并正确使用质量好的药物）
03:12
The technology is there,
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我们有技术
03:14
the infrastructure is there,
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我们有基础设施
03:16
and yet it doesn't happen.
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但是，问题却没有得到解决
03:18
So you have your million.
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那么 当你有百万美金时
03:20
How do you use your million
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你怎样花钱
03:22
to solve this last mile problem?
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才能解决“最后一英里难题”
03:24
And here's another question:
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还有另外一个问题
03:26
Malaria. Malaria kills almost
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疟疾 疟疾每年夺走
03:29
900,000 people every year,
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90万人的生命
03:32
most of them in Sub-Saharan Africa,
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大多数死者在撒哈拉以南的非洲
03:34
most of them under five.
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大多数年龄小于5岁
03:36
In fact, that is the leading cause of under-five mortality.
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事实上 疟疾是5岁下儿童的最主要死因
03:39
We already know how to kill malaria,
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我们已经知道如何治愈疟疾
03:42
but some people come to you and say,
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但有些人找到你 并对你说
03:44
"You have your millions. How about bed nets?"
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“你有几百万，不如买蚊帐吧”
03:47
Bed nets are very cheap.
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蚊帐很便宜
03:49
For 10 dollars, you can manufacture and ship
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只要10美元，你就能制造并运输
03:52
an insecticide treated bed net
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一个经过杀虫剂处理的蚊帐
03:54
and you can teach someone to use them.
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而且，你能教人们使用蚊帐
03:56
And, not only do they protect the people who sleep under them,
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此外，蚊帐不仅能保护谁在蚊帐里的人
03:59
but they have these great contagion benefits.
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而且还有巨大的防传染功效
04:01
If half of a community sleeps under a net,
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如果社区里一半的人睡在蚊帐里
04:04
the other half also benefits
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另一半也能受惠
04:06
because the contagion of the disease spread.
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因为疾病能传染、扩散
04:09
And yet, only a quarter of kids at risk sleep under a net.
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然而，只有四分之一面临疟疾风险的孩子睡在蚊帐里
04:12
Societies should be willing to go out
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社会应该愿意行动
04:14
and subsidize the net, give them for free,
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资助购买蚊帐，并且免费捐赠
04:16
or, for that matter, pay people to use them
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或者，在这个问题上，补贴那些使用蚊帐的人
04:18
because of those contagion benefits.
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因为蚊帐的防传染功效
04:20
"Not so fast," say other people.
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而另外一些人说 “别这么快”
04:22
"If you give the nets for free,
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“如果你免费提供蚊帐
04:24
people are not going to value them.
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人们不会珍惜蚊帐
04:26
They're not going to use them,
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他们不会去使用蚊帐
04:28
or at least they're not going to use them as bed nets,
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或者至少他们不会把蚊帐当蚊帐使用
04:30
maybe as fishing nets."
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而可能是当作鱼网 （蚊帐为bed net，net的意思是”网“）
04:32
So, what do you do?
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那么，你会怎样做？
04:34
Do you give the nets for free to maximize coverage,
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是免费提供蚊帐，以求最大限度的蚊帐覆盖率？
04:36
or do you make people pay
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还是要人们为蚊帐买单
04:38
in order to make sure that they really value them?
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以使他们认识到蚊帐的价值？
04:40
How do you know?
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你怎么知道？
04:42
And a third question: Education.
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第三个问题是 教育
04:44
Maybe that's the solution, maybe we should send kids to school.
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或许这才是解决之道 或许我们应该送孩子去上学
04:46
But how do you do that?
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但是你会怎么去做？
04:48
Do you hire teachers? Do you build more schools?
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你会聘请更多教师？ 你会建更多校舍？
04:50
Do you provide school lunch?
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你会提供学校午餐吗？
04:52
How do you know?
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你怎么知道哪种方法更好？
04:54
So here is the thing.
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这就是问题所在。
04:56
I cannot answer the big question,
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我无法回答那个大问题
04:58
whether aid did any good or not.
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即 援助是好是坏
05:00
But these three questions, I can answer them.
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但是，我能回答这三个小问题
05:04
It's not the Middle Ages anymore,
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现在不再是中世纪
05:06
it's the 21st century.
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而是二十一世纪
05:08
And in the 20th century,
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在二十世纪里
05:10
randomized, controlled trials
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随机的、可控的试验
05:12
have revolutionized medicine
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已经将医药革命了
05:14
by allowing us to distinguish
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因为它让我们能够区分
05:16
between drugs that work
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有效的药物
05:18
and drugs that don't work.
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和无用的药物
05:20
And you can do the same
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现在 你可以采用同样的方式：
05:22
randomized, controlled trial for social policy.
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针对社会政策的 随机的、可控的试验
05:25
You can put social innovation to the same
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你可以对社会革新施以同样的
05:27
rigorous, scientific tests
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精确而又科学的测试
05:29
that we use for drugs.
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就像我们为药物所做的那样
05:31
And in this way, you can take the guesswork
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以这种方式， 你可以把推测的成分
05:34
out of policy-making
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从政策制定中区分出来
05:36
by knowing what works,
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因为你知道了什么可行
05:38
what doesn't work and why.
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什么不可行 为什么是这样
05:40
And I'll give you some examples with those three questions.
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我会针对这三个问题举一些例子
05:44
So I start with immunization.
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首先从免疫开始
05:46
Here's Udaipur District, Rajasthan. Beautiful.
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这是印度拉贾斯坦邦的乌代布尔区 ，非常美丽
05:49
Well, when I started working there,
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当我开始在那工作时
05:51
about one percent of children
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约1%的儿童
05:53
were fully immunized.
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得到了完全免疫
05:55
That's bad, but there are places like that.
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这很糟糕 但是还有很多地方好不到哪去
05:58
Now, it's not because the vaccines are not there --
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现在，并不是因为那里没有疫苗
06:00
they are there and they are free --
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疫苗在那，而且是免费的
06:02
and it's not because parents do not care about their kids.
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也不因为父母不关心孩子
06:05
The same child that is not immunized against measles,
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一个没有免疫过麻疹的孩子
06:08
if they do get measles, parents will spend
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一旦感染麻疹 父母将要花费
06:10
thousands of rupees to help them.
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数千卢用于治疗
06:12
So you get these empty village subcenters
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现在 你看到这些空荡荡的乡村中心
06:14
and crowded hospitals.
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和拥挤的医院
06:16
So what is the problem?
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那么问题在哪？
06:18
Well, part of the problem, surely, is people do not fully understand.
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部分问题当然是人们不太懂
06:21
After all, in this country as well,
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毕竟在这个国家
06:23
all sorts of myths and misconceptions
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有各种关于疟疾的
06:25
go around immunization.
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传说和误解.
06:28
So if that's the case, that's difficult,
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如果这是问题所在, 很麻烦
06:30
because persuasion is really difficult.
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因为很难说服人们.
06:33
But maybe there is another problem as well.
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但是 或许还有另外一个问题.
06:35
It's going from intention to action.
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人们开始从关注它到采取行动
06:38
Imagine you are a mother
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想象下你是位母亲
06:40
in Udaipur District, Rajasthan.
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就生活在拉贾斯坦邦的乌代布尔区
06:42
You have to walk a few kilometers to get your kids immunized.
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你不得不不行几公里才能让孩子得到免疫
06:45
And maybe when you get there, what you find is this:
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或许当你到达免疫地点时 你会发现
06:47
The subcenter is closed. Ao you have to come back,
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副中心关门了 那么你就不得不打道回府
06:49
and you are so busy and you have so many other things to do,
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如果你很忙 你有很多事要做
06:52
you will always tend to postpone and postpone,
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你将一直拖延拖延
06:54
and eventually it gets too late.
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直到有一天已经太迟了.
06:56
Well, if that's the problem, then that's much easier.
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如果这是问题所在的话 倒是简单很多
06:59
Because A, we can make it easy,
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因为: A 我们能让免疫更容易
07:02
and B, we can maybe
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B 我们或许
07:04
give people a reason to act today,
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能给人们一个今天就行动的理由
07:06
rather than wait till tomorrow.
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而不是等到明天.
07:08
So these are simple ideas, but we didn't know.
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这是很简单的想法 但过去我们不知道.
07:10
So let's try them.
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那么让我们将这些想法付诸行动.
07:12
So what we did is we did a randomized, controlled trial
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我们过去的是 随机的、可控的试验
07:15
in 134 villages in Udaipur Districts.
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在拉贾斯坦邦的乌代布尔区的134个村庄
07:17
So the blue dots
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这些蓝点
07:19
are selected randomly.
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是随机选定的.
07:21
We made it easy -- I'll tell you how in a moment.
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我们的做法很简单 一会我就告诉你们.
07:24
In the red dots, we made it easy
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在红点处 我们简单地
07:26
and gave people a reason to act now.
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告诉人们一个今天就行动的理由。
07:28
The white dots are comparisons, nothing changed.
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白点处是作为对比，什么也没变
07:31
So we make it easy by organizing
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我们简单地组织
07:33
this monthly camp where people can
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每月营地，在这里人们可以
07:35
get their kids immunized.
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让孩子得到免疫
07:37
And then you make it easy
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然后你就简单地
07:39
and give a reason to act now
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告诉人们一个今天就行动的理由
07:41
by adding a kilo of lentils for each immunization.
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通过给每次免疫一公斤扁豆的补助
07:44
Now, a kilo of lentils is tiny.
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现在 一公斤扁豆真是微不足道。
07:47
It's never going to convince anybody
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你永远也不会说服任何人
07:49
to do something that they don't want to do.
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去做他们不想做的事。
07:51
On the other hand, if your problem is you tend to postpone,
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另一方面 如果你的问题是你老是拖延，
07:54
then it might give you a reason to act today
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那就给你个今天就行动的理由
07:56
rather than later.
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而不是以后再去做
07:58
So what do we find?
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那么我们发现了什么？
08:00
Well, beforehand, everything is the same.
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起初 一切如故
08:02
That's the beauty of randomization.
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这就是随机试验的好处
08:04
Afterwards,
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后来
08:06
the camp -- just having the camp --
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这些营地 仅仅是每月营地
08:08
increases immunization from six percent to 17 percent.
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将免疫率从6%增长到17%
08:10
That's full immunization.
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是指完全免疫
08:12
That's not bad, that's a good improvement.
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还不错，很大的进步
08:14
Add the lentils and you reach to 38 percent.
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加了扁豆后 数字达到了38%
08:17
So here you've got your answer.
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现在你就知道答案了
08:19
Make it easy and give a kilo of lentils,
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简单点 给一公斤扁豆
08:21
you multiply immunization rate by six.
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就将免疫率乘以6
08:24
Now, you might say, "Well, but it's not sustainable.
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现在 你会说 ”很好，可这是不可持续的
08:26
We cannot keep giving lentils to people."
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我们不能总是给扁豆”
08:28
Well, it turns out it's wrong economics,
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结果是 这是错误的经济学
08:30
because it is cheaper
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因为给扁豆
08:32
to give lentils than not to give them.
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比不给扁豆要便宜
08:34
Since you have to pay for the nurse anyway,
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既然 你总是要为护士付费
08:36
the cost per immunization
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每次免疫费用
08:38
ends up being cheaper if you give incentives than if you don't.
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最终是给激励时比不给时要便宜
08:42
How about bed nets?
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蚊帐又该如何？
08:44
Should you give them for free, or should you ask people to pay for them?
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你是免费发放 还是让人们付费？
08:47
So the answer hinges
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答案取决于
08:49
on the answer to three simple questions.
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三个简单问题的答案
08:51
One is: If people must pay for a bed net,
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第一个问题是如果人们必须为蚊帐付费
08:54
are they going to purchase them?
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他们还会买吗？
08:56
The second one is:
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第二个问题是
08:58
If I give bed nets for free,
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如果蚊帐是免费的
09:00
are people going to use them?
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人们还会用吗？
09:02
And the third one is:
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第三个问题是
09:04
Do free bed nets discourage future purchase?
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免费蚊帐会导致日后不再购买蚊帐吗？
09:06
The third one is important
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第三个问题很重要
09:08
because if we think people get used to handouts,
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因为 如果我们认为人们习惯了救济后
09:11
it might destroy markets to distribute free bed nets.
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将会破坏发放免费蚊帐的市场
09:14
Now this is a debate that has generated
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现在 这个争论已经
09:16
a lot of emotion and angry rhetoric.
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带来了很多感情和愤怒的言辞。
09:19
It's more ideological than practical,
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这更理想主义而非实用主义，
09:21
but it turns out it's an easy question.
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但又回答了一个简单的问题。
09:23
We can know the answer to this question.
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我们可以知道问题的答案
09:25
We can just run an experiment.
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我们只要做下试验
09:27
And many experiments have been run, and they all have the same results,
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很多试验 都有相同的结果
09:29
so I'm just going to talk to you about one.
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接下来 我会给你们讲一个
09:32
And this one that was in Kenya,
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这个试验是在肯尼亚做的
09:34
they went around and distributed to people
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他们到处走动 分发给村民
09:36
vouchers, discount vouchers.
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优惠券 折扣券
09:38
So people with their voucher
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然后 人们用优惠券
09:40
could get the bed net in the local pharmacy.
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可以在当地的要点买到蚊帐
09:42
And some people get 100 percent discount,
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有些人得到100%折扣
09:45
and some people get 20 percent discounts,
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有些是20%折扣
09:47
and some people get 50 percent discount, etc.
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有些事50%折扣 等等
09:50
And now we can see what happens.
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现在我们可以看看发生了什么
09:52
So, how about the purchasing?
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若是要购买会如何
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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当人们不得不为蚊帐付费时
09:58
the coverage rate really falls down a lot.
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蚊帐覆盖率大幅下降
10:01
So even with partial subsidy,
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即使有部分补助-
10:03
three dollars is still not the full cost of a bed net,
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3美元依然不是蚊帐的完全花费
10:06
and now you only have 20 percent of the people with the bed nets,
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现在你只有20%的人拥有蚊帐
10:08
you lose the health immunity, that's not great.
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你失去了[覆盖率] 那样不好
10:11
Second thing is, how about the use?
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第二件事是 年轻人会如何
10:13
Well, the good news is, people, if they have the bed nets,
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好消息是 当人们拥有蚊帐时
10:15
will use the bed nets regardless of how they got it.
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他们会使用蚊帐 不管蚊帐是如何得到的
10:18
If they get it for free, they use it.
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他们免费得到蚊帐 会使用
10:20
If they have to pay for it, they use it.
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他们付费得到蚊帐 也会使用
10:22
How about the long term?
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长期情况如何呢？
10:24
In the long term,
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长远看来
10:26
people who got the free bed nets,
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得到免费蚊帐的人们
10:28
one year later, were offered the option
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一年后 面临花两美元
10:30
to purchase a bed net at two dollars.
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买一个蚊帐的选择
10:33
And people who got the free one
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免费获得蚊帐的人们
10:35
were actually more likely to purchase the second one
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实际上更可能买第二个蚊帐
10:38
than people who didn't get a free one.
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相比没得到免费蚊帐的人而言
10:40
So people do not get used to handouts; they get used to nets.
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所以 人们没有习惯于救济 而是习惯于蚊帐！
10:43
Maybe we need to give them a little bit more credit.
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或许我们应该更相信他们
10:48
So, that's for bed nets. So you will think, "That's great.
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那些就是关于蚊帐的 你会想“太好了
10:50
You know how to immunize kids, you know how to give bed nets."
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你知道怎样免疫 你知道怎样发放蚊帐”
10:53
But what politicians need is a range of options.
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但是政客们需要的是一组选择
10:56
They need to know: Out of all the things I could do,
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他们需要知道： 在所有这些我能做的事当中
10:59
what is the best way to achieve my goals?
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哪一个是能最好地实现目标的方式？
11:02
So suppose your goal is to get kids into school.
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假如你的目标是让孩子们上学
11:05
There are so many things you could do. You could pay for uniforms,
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有这么多事可做 你可以为制服买单
11:08
you could eliminate fees, you could build latrines,
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你可以降低费用 你可以建造公厕
11:10
you could give girls sanitary pads, etc., etc.
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你可以给女孩提供卫生垫 等等
11:13
So what's the best?
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那么最好的是什么？
11:15
Well, at some level, we think
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某种程度上而言 我们认为
11:17
all of these things should work.
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所有这些事都该做
11:19
So, is that sufficient? If we think they should work intuitively,
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那么 这些足够吗？ 比如, 假如我们凭直觉认为这些应该有效
11:21
should we go for them?
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我们应该去做这些事吗？
11:23
Well, in business, that's certainly not the way we would go about it.
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在商业里 这显然不是我们做事的方式
11:27
Consider for example
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考虑下这个例子
11:29
transporting goods.
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运输货物
11:31
Before the canals were invented
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在运河被发明之前
11:33
in Britain before the Industrial Revolution,
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英国在工业革命前
11:36
goods used to go on horse carts.
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货物是通过马车运输
11:38
And then canals were built,
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接着运河被修建后
11:40
and with the same horseman and the same horse,
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用同样的马夫和同样的马匹
11:43
you could carry ten times as much cargo.
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你可以运输十倍于之前的货物
11:46
So should they have continued
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那么 他们应该继续
11:48
to carry the goods on the horse carts, on the ground,
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用马车在路上运输货物吗？
11:51
that they would eventually get there?
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反正他们最终总是能到达目的地
11:53
Well, if that had been the case,
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如果 现实是这样
11:55
there would have been no Industrial Revolution.
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就不会发生工业革命
11:57
So why shouldn't we do the same with social policy?
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那么 为什么我们不应以同样方式来制定社会政策？
12:00
In technology, we spend so much time
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在科技领域 我们花费了大量时间
12:02
experimenting, fine-tuning,
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做实验 调节
12:04
getting the absolute cheapest way to do something,
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获得绝对最便宜的方式去做某事
12:06
so why aren't we doing that with social policy?
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那么 为什么我们没有以同样方式来制定社会政策？
12:09
Well, with experiments, what you can do
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通过做实验 你可以做到的是
12:11
is answer a simple question.
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回答一个简单的问题
12:13
Suppose you have 100 dollars to spend
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假如你有100美元
12:15
on various interventions.
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可以用于各种干预措施
12:17
How many extra years of education
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用你的几百美元
12:19
do you get for your hundred dollars?
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可以得到多少年额外的教育？
12:21
Now I'm going to show you
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现在我会告诉你
12:23
what we get with various education interventions.
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各种教育干预能带来什么
12:27
So the first ones are if you want the usual suspects,
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最先的答案 是一些普遍的假设：
12:29
hire teachers, school meals,
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请老师 学校午餐
12:31
school uniforms, scholarships.
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学校制服 奖学金
12:33
And that's not bad. For your hundred dollars,
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这都不错 用你的一百美金
12:35
you get between one and three extra years of education.
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你可以得到一到三年的额外教育
12:39
Things that don't work so well is bribing parents,
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不太好的事是贿赂家长
12:41
just because so many kids are already going to school
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仅仅因为很多孩子已经开始上学
12:44
that you end up spending a lot of money.
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你终止了花费大量金钱
12:46
And here are the most surprising results.
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这儿是最让人惊讶的结果
12:49
Tell people the benefits of education,
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告诉人们教育的益处
12:52
that's very cheap to do.
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这佯做很便宜
12:54
So for every hundred dollars you spend doing that,
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你花费在这件事的每一百美元
12:57
you get 40 extra years of education.
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你将得到40年额外教育
13:00
And, in places where there are worms,
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在那些有寄生虫的地方
13:02
intestinal worms,
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蛔虫
13:04
cure the kids of their worms.
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治疗有蛔虫的小孩
13:06
And for every hundred dollars,
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用每一百美元
13:08
you get almost 30 extra years of education.
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你将得到几乎30年的额外教育
13:11
So this is not your intuition,
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这不复合你的直觉
13:13
this is not what people would have gone for,
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这不是人们希望的
13:15
and yet, these are the programs that work.
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然而 这些项目很有效
13:18
We need that kind of information, we need more of it,
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我们需要那样的信息 我们需要更多
13:20
and then we need to guide policy.
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然后 我们需要引导政策
13:24
So now, I started from the big problem, and I couldn't answer it.
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好的 我是从那个大问题开始的 我不能回答它
13:27
And I cut it into smaller questions,
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然后 我将它分为几个小问题
13:30
and I have the answer to these smaller questions.
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而我能回答这些小问题
13:32
And they are good, scientific, robust answers.
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这些回答是很好的、科学的、有力的回答
13:36
So let's go back to Haiti for a moment.
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我们回过头来谈谈海地
13:39
In Haiti, about 200,000 people died --
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在海地 大约20万人丧身
13:43
actually, a bit more by the latest estimate.
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事实上 最新的估计比这个数字还要多
13:45
And the response of the world was great:
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世界的反应时强烈的
13:47
Two billion dollars got pledged just last month,
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过去一个月 募集了20亿美元
13:51
so that's about 10,000 dollars per death.
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大约是 每一个死亡1万美元
13:53
That doesn't sound like that much when you think about it.
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你仔细想想 其实这并不像听起来那么多
13:56
But if we were willing to spend 10,000 dollars
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但是 如果我们愿意为每个去世的小于5岁的孩子
13:59
for every child under five who dies,
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花费1万美元
14:02
that would be 90 billion per year
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那将是每年900美元
14:05
just for that problem.
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仅仅是为那个问题
14:07
And yet it doesn't happen.
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然而 这并没有发生
14:09
So, why is that?
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那 这是为什么呢？
14:11
Well, I think what part of the problem is that,
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我认为部分问题在于
14:13
in Haiti, although the problem is huge,
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尽管海地的问题很大
14:15
somehow we understand it, it's localized.
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可是我们总能懂一些 我们就能定位问题
14:17
You give your money to Doctors Without Borders,
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你捐钱给无国界医生组织
14:19
you give your money to Partners In Health,
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你捐钱给健康伙伴组织(Partners in Health)
14:21
and they'll send in the doctors, and they'll send in the lumber,
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他们会送医生过去 他们会送物品过去
14:24
and they'll helicopter things out and in.
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他们会用直升飞机运东西进进出出
14:27
And the problem of poverty is not like that.
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但是贫困的问题并非如此
14:29
So, first, it's mostly invisible;
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首先 它通常是看不见的
14:31
second, it's huge;
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其次 它是很严重的
14:33
and third, we don't know whether we are doing the right thing.
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最后 我们不清楚我们所做的是否正确
14:36
There's no silver bullet.
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没有任何绝招可用
14:38
You cannot helicopter people out of poverty.
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你不能用直升飞机将人们从贫困中运出
14:40
And that's very frustrating.
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这真是让人沮丧
14:42
But look what we just did today.
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但是看看我们今天所做的
14:45
I gave you three simple answers to three questions:
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我给你们三个问题的三个简单答案
14:48
Give lentils to immunize people,
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让免疫[更便利]
14:50
provide free bed nets, deworm children.
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提供免费蚊帐 给孩子打蛔虫
14:52
With immunization or bed nets,
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通过免疫或者蚊帐
14:54
you can save a life for 300 dollars per life saved.
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你可以用300美元拯救一条生命
14:57
With deworming, you can get
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通过打蛔虫 你可以用300美元
14:59
an extra year of education for three dollars.
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得到一年额外的教育
15:02
So we cannot eradicate poverty just yet,
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我们不能立刻消除贫困
15:05
but we can get started.
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但是我们可以开始行动
15:07
And maybe we can get started small
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或许我们能以那些
15:09
with things that we know are effective.
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我们知道是有效的方式开始
15:12
Here's an example of how this can be powerful.
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这个例子告诉我们这样做多么强有力
15:14
Deworming.
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打蛔虫
15:16
Worms have a little bit of a problem grabbing the headlines.
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蛔虫不会引起新闻头条的一丝主义
15:18
They are not beautiful and don't kill anybody.
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他们不漂亮 他们不杀死人
15:21
And yet, when the young global leader in Davos
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然而 当年轻的全球领袖 在达沃斯
15:23
showed the numbers I gave you,
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展示这些我告诉你们的数字时
15:25
they started Deworm the World.
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他们开始了”世界除虫“行动
15:27
And thanks to Deworm the World,
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幸亏有这个世界除虫行动
15:29
and the effort of many country governments and foundations,
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以及很多国家政府和基金会的努力
15:31
20 million school-aged children got dewormed in 2009.
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2009年有2千万学龄儿童得到除虫
15:34
So this evidence is powerful.
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这个证据是强有力的
15:36
It can prompt action.
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它能推动行动
15:38
So we should get started now.
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我们现在就应开始行动
15:40
It's not going to be easy.
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现在 这不是件容易的事
15:42
It's a very slow process.
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这是很漫长的过程
15:44
You have to keep experimenting, and sometimes ideology
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你必须坚持试验 有时候
15:46
has to be trumped by practicality.
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必须用实用性来鼓吹想法
15:48
And sometimes what works somewhere doesn't work elsewhere.
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有时候 在此地有效的方式在彼处失效
15:51
So it's a slow process,
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这是很漫长的过程
15:53
but there is no other way.
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但是有其他放肆
15:55
These economics I'm proposing,
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我所建议的经济学
15:57
it's like 20th century medicine.
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就像20实际的药物
15:59
It's a slow, deliberative process
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这是一个漫长，很慎重
16:01
of discovery.
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发现过程
16:03
There is no miracle cure,
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没有魔法疗法
16:05
but modern medicine is saving
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但是现代药物
16:07
millions of lives every year,
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每年都在挽救数以百万计的生命
16:09
and we can do the same thing.
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而我们可以做到同样的事
16:13
And now, maybe, we can go back to the bigger question
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现在 或许我们能回归到那个
16:16
that I started with at the beginning.
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我一开始就提出的大问题
16:19
I cannot tell you
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我不能告诉你
16:21
whether the aid we have spent in the past has made a difference,
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过去的援助花费是否起了作用
16:24
but can we come back here in 30 years
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但是 30年后我们可以回到这里
16:27
and say, "What we have done,
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然后说 ”我们所做的一切
16:30
it really prompted a change for the better."
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真的促进了事情往好的方向改变“
16:33
I believe we can and I hope we will.
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我相信我们可以做到 我希望我们能够做到
16:35
Thank you.
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谢谢
16:37
(Applause)
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(掌声)
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