TEDGlobal 2012
Daphne Koller: What we're learning from online education
Daphne Koller: 我们从在线教育学到了什么
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Daphne Koller正在"引诱"顶尖大学去把他们有意思的课程做成免费的网络教育----不光是一项服务,而且是一项研究人们如何学习的课题. 每次敲键盘,每个小测验,同龄人之间的讨论和自己批改的作业创立了一个前所未有的数据库,让我们了解知识是怎么处理的,而且最重要的是,怎么被吸取的.
Daphne Koller - Educator
With Coursera, Daphne Koller and co-founder Andrew Ng are bringing courses from top colleges online, free, for anyone who wants to take them. Full bio
With Coursera, Daphne Koller and co-founder Andrew Ng are bringing courses from top colleges online, free, for anyone who wants to take them. Full bio
Double-click the English transcript below to play the video.
00:16
Like many of you, I'm one of the lucky people.
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跟你们在座的人一样,我也是一个幸运的人.
00:19
I was born to a family where education was pervasive.
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我生于一个教育是很普遍的家庭
00:23
I'm a third-generation PhD, a daughter of two academics.
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我是我们家里的第三代博士,我父母都是做学问的
00:27
In my childhood, I played around in my father's university lab.
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童年时,我在我父亲的大学实验室里玩耍
00:31
So it was taken for granted that I attend some of the best universities,
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因此毫无疑问我最后上了一些最好的大学
00:35
which in turn opened the door to a world of opportunity.
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这样就为我打开一扇巨大的机会之门
00:38
Unfortunately, most of the people in the world are not so lucky.
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不幸的是,这世上大多数的人并没那么幸运
00:42
In some parts of the world, for example, South Africa,
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在世界的某些地方,比如说,在南非,
00:46
education is just not readily accessible.
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教育确实是很难得到
00:48
In South Africa, the educational system was constructed
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在南非,教育系统是在种族隔离时期
00:51
in the days of apartheid for the white minority.
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为少数白人而建造的
00:54
And as a consequence, today there is just not enough spots
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因此,如今对于那些想要并且应当得到
00:57
for the many more people who want and deserve a high quality education.
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高质量的教育的人来说却没有足够的位置
01:01
That scarcity led to a crisis in January of this year
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今年一月,教育机会上的贫乏导致了在
01:05
at the University of Johannesburg.
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约翰尼斯堡大学的一个危机
01:06
There were a handful of positions left open
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在正常的录取工作下还有很多位置是空的,
01:09
from the standard admissions process, and the night before
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而在他们准备打开这些位置
01:11
they were supposed to open that for registration,
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让别人来注册的前夜,
01:14
thousands of people lined up outside the gate in a line a mile long,
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成千上万的人在门外排起了一英里长的队伍
01:18
hoping to be first in line to get one of those positions.
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希望自己是第一个进去得到这个位置的
01:22
When the gates opened, there was a stampede,
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当门打开时,出现了踩踏事件
01:24
and 20 people were injured and one woman died.
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结果导致20人受伤,1个女人死亡
01:28
She was a mother who gave her life
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她是一位母亲,试图为她儿子争取一个过上好生活
01:30
trying to get her son a chance at a better life.
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的机会
01:34
But even in parts of the world like the United States
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即使在像美国这样的地区
01:37
where education is available, it might not be within reach.
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尽管教育机会开放,但仍然有可能无法垂手可得
01:41
There has been much discussed in the last few years
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过去几年有很多人在讨论
01:44
about the rising cost of health care.
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医疗保险的价格上升
01:46
What might not be quite as obvious to people
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对于人们来说可能不明显的是,在这段时间里
01:49
is that during that same period the cost of higher education tuition
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高等教育的消费支出
01:53
has been increasing at almost twice the rate,
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几乎在以两倍的速度增长
01:55
for a total of 559 percent since 1985.
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自1985年来上涨了559%
02:00
This makes education unaffordable for many people.
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这使得很多人无法负担教育费用
02:04
Finally, even for those who do manage to get the higher education,
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即使对于很多有办法得到高等教育的人,
02:08
the doors of opportunity might not open.
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机会的大门也许不会向他们打开
02:11
Only a little over half of recent college graduates
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只有仅仅过半的在美国
02:14
in the United States who get a higher education
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接受高等教育的大学研究生
02:16
actually are working in jobs that require that education.
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实际工作在要求研究生学位的岗位上
02:19
This, of course, is not true for the students
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当然,这对于从高等院校毕业的学生
02:21
who graduate from the top institutions,
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来说肯定不是真的
02:23
but for many others, they do not get the value
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但是对于其他人来说就是,他们没有得到
02:26
for their time and their effort.
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他们付出的时间和努力所带来的价值
02:29
Tom Friedman, in his recent New York Times article,
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Tom Friedman,在他最近的纽约时报的文章中（以他人所不能的方式）
02:32
captured, in the way that no one else could, the spirit behind our effort.
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抓住了在我们在努力背后的精神
02:37
He said the big breakthroughs are what happen
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他说巨大的突破是在当突然可能的事情
02:40
when what is suddenly possible meets what is desperately necessary.
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满足急切需要的事情时发生的
02:44
I've talked about what's desperately necessary.
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我已经说了什么是急切需要的了
02:46
Let's talk about what's suddenly possible.
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现在让我讲讲什么是突然可能的
02:49
What's suddenly possible was demonstrated by
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这个其实已经被斯坦福大学三个大课
02:52
three big Stanford classes,
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所展示了
02:54
each of which had an enrollment of 100,000 people or more.
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每种课都是100000人以上在听
02:58
So to understand this, let's look at one of those classes,
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因此为了理解这一点,我们看看其中一个
03:01
the Machine Learning class offered by my colleague
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由我一个同事和Andrew Ng教授
03:03
and cofounder Andrew Ng.
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共同创办的机器研究课程
03:05
Andrew teaches one of the bigger Stanford classes.
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Andrew是教授斯坦福的大课程的
03:07
It's a Machine Learning class,
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是机器研究课程
03:08
and it has 400 people enrolled every time it's offered.
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每回都有400多人参加
03:12
When Andrew taught the Machine Learning class to the general public,
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而当Andrew把这门课传播到公众当中,
03:15
it had 100,000 people registered.
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100000人注册了
03:18
So to put that number in perspective,
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就这样来说吧,
03:20
for Andrew to reach that same size audience
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为了让他通过教授斯坦福课程来
03:22
by teaching a Stanford class,
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影响到那么多人
03:24
he would have to do that for 250 years.
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他得用250年时间
03:28
Of course, he'd get really bored.
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当然,他肯定会无聊死
03:31
So, having seen the impact of this,
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因此在见识到这个事情的影响之后
03:34
Andrew and I decided that we needed to really try and scale this up,
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Andrew和我决定我们得做大这件事
03:37
to bring the best quality education to as many people as we could.
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去尽可能的为更多人带来最优质的教育
03:41
So we formed Coursera,
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因此我们创建了Coursera(译者注:Coursera.org 是一个提供免费网络课程的网站)
03:43
whose goal is to take the best courses
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目地是为了让人们从最好的大学、最好的导师
03:46
from the best instructors at the best universities
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中学到最好的课程
03:49
and provide it to everyone around the world for free.
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而且免费提供给世界各地的人
03:53
We currently have 43 courses on the platform
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我们目前在平台上有43个课程
03:56
from four universities across a range of disciplines,
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来自4所大学,有各种各样的学科
03:59
and let me show you a little bit of an overview
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让我给大家看看这个网站
04:01
of what that looks like.
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大概是什么样子吧
04:04
(Video) Robert Ghrist: Welcome to Calculus.
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(视频)Robert Ghrist: 欢迎来到微积分课程
04:05
Ezekiel Emanuel: Fifty million people are uninsured.
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Ezekiel Emanuel: 有5千万人没有保险
04:07
Scott Page: Models help us design more effective institutions and policies.
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Scott Page: 模型帮助我们去设计更有效的制度和政策
04:10
We get unbelievable segregation.
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我们有不可置信的种族分离
04:13
Scott Klemmer: So Bush imagined that in the future,
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Scot Klemmer: 因此布什想象到,在未来,
04:15
you'd wear a camera right in the center of your head.
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你会在你头正中间带一架照相机
04:17
Mitchell Duneier: Mills wants the student of sociology to develop the quality of mind ...
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Mitchell Duneier: Mills想要社会学的学生们培养他们思维的质量
04:21
RG: Hanging cable takes on the form of a hyperbolic cosine.
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RG: 悬挂的电线呈双曲线型的余弦函数形状
04:25
Nick Parlante: For each pixel in the image, set the red to zero.
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Nick Parlante: 对于图像中的每一个像素, 将红色设置为0
04:28
Paul Offit: ... Vaccine allowed us to eliminate polio virus.
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Paul Offit: 疫苗可以帮我们去消灭小儿麻痹症的病毒
04:31
Dan Jurafsky: Does Lufthansa serve breakfast and San Jose? Well, that sounds funny.
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Dan Jurafsky: 德国汉莎航空公司提供早餐和San Jose吗?(译者注: San Jose是圣约瑟餐馆) 嗯，那听起来挺有意思
04:35
Daphne Koller: So this is which coin you pick, and this is the two tosses.
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Daphne Koller: 这就是你选出来的硬币,这是两次投掷的结果
04:38
Andrew Ng: So in large-scale machine learning, we'd like to come up with computational ...
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Andrew Ng: 因此在大规模的机器研究中,我们希望得出计算型的....
04:42
(Applause)
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(鼓掌)
04:47
DK: It turns out, maybe not surprisingly,
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DK: 结果呢,可能不是很令人吃惊,
04:50
that students like getting the best content
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学生们都喜欢免费从最好的大学得到
04:52
from the best universities for free.
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最好的课程内容
04:55
Since we opened the website in February,
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自从我们在二月创建了这个网站后,
04:57
we now have 640,000 students from 190 countries.
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我们现在已经有来自190个国家的640000名学生
05:02
We have 1.5 million enrollments,
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我们有150万次的申请
05:04
6 million quizzes in the 15 classes that have launched
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15个已经开讲的课程里的600万个小测验
05:07
so far have been submitted, and 14 million videos have been viewed.
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已被提交,1400万的视频已被观看
05:12
But it's not just about the numbers,
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不过这不仅跟数字有关
05:14
it's also about the people.
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还跟人有关
05:16
Whether it's Akash, who comes from a small town in India
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不管是来自印度的一个小镇
05:19
and would never have access in this case
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绝不会得到斯坦福水准的
05:21
to a Stanford-quality course
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课程,而且也无法支付那些课程的
05:22
and would never be able to afford it.
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Akash
05:25
Or Jenny, who is a single mother of two
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或者是两个孩子的单身妈妈
05:27
and wants to hone her skills
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想在家里学点技能
05:29
so that she can go back and complete her master's degree.
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然后回去完成她的硕士学位的Jenny
05:32
Or Ryan, who can't go to school,
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还是Ryan, 他不能上学
05:35
because his immune deficient daughter
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因为他的无抵抗力的女儿
05:37
can't be risked to have germs come into the house,
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使他必须待在家里确保没有细菌
05:40
so he couldn't leave the house.
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进入房间
05:42
I'm really glad to say --
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我很高兴地可以说--
05:44
recently, we've been in correspondence with Ryan --
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最近,我们在与Ryan联系
05:46
that this story had a happy ending.
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最后这个故事有了一个很好的结局
05:48
Baby Shannon -- you can see her on the left --
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Shannon宝贝--你可以从左边看到她
05:50
is doing much better now,
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现在变得好多了
05:51
and Ryan got a job by taking some of our courses.
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而且Ryan由于上了我们提供的一些课,他得到了一份工作
05:56
So what made these courses so different?
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那到底是什么使得这些课程与众不同呢?
05:58
After all, online course content has been available for a while.
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毕竟,在线课程已经有很长一段时间了
06:02
What made it different was that this was real course experience.
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但不同的是这些都是真正的上课体验
06:05
It started on a given day,
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从固定的一天开始,
06:07
and then the students would watch videos on a weekly basis
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然后学生每周必须去观看视频
06:11
and do homework assignments.
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然后做家庭作业
06:12
And these would be real homework assignments
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而这些都是真正的家庭作业
06:14
for a real grade, with a real deadline.
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有真正的成绩和截止日期
06:18
You can see the deadlines and the usage graph.
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你看以看到截止日期和使用情况的图像
06:20
These are the spikes showing
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这些顶端表明
06:22
that procrastination is global phenomenon.
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耽搁是一个全球现象
06:26
(Laughter)
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(笑声)
06:28
At the end of the course,
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在每门课结束后
06:30
the students got a certificate.
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学生们会得到一个证书
06:32
They could present that certificate
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他们可以把证书给雇主看
06:34
to a prospective employer and get a better job,
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然后得到一个更好的工作
06:36
and we know many students who did.
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而我们知道很多学生都这么做了
06:38
Some students took their certificate
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很多学生拿着证书
06:40
and presented this to an educational institution at which they were enrolled
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给了他们在读的院校
06:43
for actual college credit.
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索要真正的大学学分
06:45
So these students were really getting something meaningful
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因此这些学生为他们所付出的时间和努力
06:47
for their investment of time and effort.
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的确在得到一些有意义的东西
06:50
Let's talk a little bit about some of the components
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让我们谈谈在课程里面一些
06:52
that go into these courses.
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部分内容吧
06:54
The first component is that when you move away
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第一个就是当你
06:57
from the constraints of a physical classroom
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摆脱了在教室里的束缚
06:59
and design content explicitly for an online format,
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和为在线课程明确地设计内容的时候
07:02
you can break away from, for example,
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你可以不再使用,比如说
07:05
the monolithic one-hour lecture.
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单调的一小时讲座的模式
07:07
You can break up the material, for example,
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你可以将材料,比如说,
07:09
into these short, modular units of eight to 12 minutes,
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分成8到12分钟的短的单元
07:12
each of which represents a coherent concept.
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每一个都代表一个连贯的概念
07:15
Students can traverse this material in different ways,
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学生可以用不同方式来反复研究这个材料
07:18
depending on their background, their skills or their interests.
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取决于他们的背景,技能,和兴趣
07:21
So, for example, some students might benefit
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比如说,一些学生会从
07:24
from a little bit of preparatory material
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一点点的准备材料中收益
07:27
that other students might already have.
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但其他学生可能已经了解了
07:29
Other students might be interested in a particular
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其他学生可能对其中的一个话题
07:31
enrichment topic that they want to pursue individually.
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感兴趣, 从而他们想去单独探索它
07:34
So this format allows us to break away
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因此这种模式可以让我们逃出
07:38
from the one-size-fits-all model of education,
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“一刀切” 的教育方法
07:40
and allows students to follow a much more personalized curriculum.
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并且允许学生去遵循一个更个性化的课程安排
07:44
Of course, we all know as educators
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当然,我们都知道作为教育者,
07:47
that students don't learn by sitting and passively watching videos.
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学生们干坐着看视频是学不到什么东西的.
07:50
Perhaps one of the biggest components of this effort
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或许这努力当中最大的部分
07:53
is that we need to have students
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是需要让这些学生通过
07:56
who practice with the material
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材料的练习去
07:58
in order to really understand it.
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真正的理解课程
08:01
There's been a range of studies that demonstrate the importance of this.
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有很多研究表明这一方面的重要性,
08:04
This one that appeared in Science last year, for example,
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比如说,去年在科学杂志上出现的一篇,
08:07
demonstrates that even simple retrieval practice,
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表明了即使是简单的重复小练习
08:10
where students are just supposed to repeat
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只需要学生重复
08:13
what they already learned
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他们刚刚学到的东西
08:14
gives considerably improved results
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会带来很大的提高效果
08:16
on various achievement tests down the line
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不管是在各种成绩测试
08:18
than many other educational interventions.
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还是其他教育性的打断
08:23
We've tried to build in retrieval practice into the platform,
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我们在尝试在平台中去建立一个回顾性的测试
08:25
as well as other forms of practice in many ways.
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以及其他各种方式的练习
08:28
For example, even our videos are not just videos.
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比如说,我们的视频不光是简单的视频
08:32
Every few minutes, the video pauses
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每过几分钟,视频就会暂停下来
08:34
and the students get asked a question.
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然后学生必须回答一个问题
08:36
(Video) SP: ... These four things. Prospect theory, hyperbolic discounting,
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(视频)SP: ...这四样东西,预期理论,双曲贴现,
08:38
status quo bias, base rate bias. They're all well documented.
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现状偏差,基准利率偏差.这些都被很好地记录下来
08:41
So they're all well documented deviations from rational behavior.
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因此他们都是从理性的行为中很好地记录下来的偏差
08:44
DK: So here the video pauses,
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DK: 在这视频就暂停了
08:46
and the student types in the answer into the box
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然后学生需要在方框里输入答案
08:48
and submits. Obviously they weren't paying attention.
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然后提交.显然这些学生在走神儿
08:51
(Laughter)
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(笑声)
08:52
So they get to try again,
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所以他们又试了一次
08:54
and this time they got it right.
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而这回他们答对了
08:57
There's an optional explanation if they want.
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这还有一个参考的解释, 如果他们想要的话
08:59
And now the video moves on to the next part of the lecture.
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然后现在视频才继续进行到讲座的下一部分
09:03
This is a kind of simple question
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这是一种我作为一名导师
09:05
that I as an instructor might ask in class,
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可能会在课堂上问的简单的问题
09:07
but when I ask that kind of a question in class,
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不过当我在真正的课堂上问的时候,
09:10
80 percent of the students
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80%的学生
09:11
are still scribbling the last thing I said,
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还在琢磨我前面说的话
09:13
15 percent are zoned out on Facebook,
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15%的学生都沉浸在Facebook里,
09:16
and then there's the smarty pants in the front row
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然后坐在前排的聪明蛋
09:19
who blurts out the answer
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直接在其他人还没机会思考的之前
09:20
before anyone else has had a chance to think about it,
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一口报出正确答案.
09:22
and I as the instructor am terribly gratified
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然后作为老师我极度满足
09:25
that somebody actually knew the answer.
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竟然有人知道答案
09:27
And so the lecture moves on before, really,
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因此我就继续往下讲了,所以你可以看到,
09:29
most of the students have even noticed that a question had been asked.
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大多数学生只是注意到了老师问了个问题...
09:33
Here, every single student
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在这,每个学生
09:36
has to engage with the material.
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必须与材料接洽
09:38
And of course these simple retrieval questions
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当然不光是这些回顾性的
09:40
are not the end of the story.
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小问题
09:42
One needs to build in much more meaningful practice questions,
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应该有更多的有意义的练习性问题
09:45
and one also needs to provide the students with feedback
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而且还应该在那些问题上
09:47
on those questions.
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对学生有所回馈
09:49
Now, how do you grade the work of 100,000 students
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那如果没有10000助教的话,
09:52
if you do not have 10,000 TAs?
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怎么样才能批改100000名学生的作业呢?
09:55
The answer is, you need to use technology
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答案是,你得使用科技
09:57
to do it for you.
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来帮助你
09:59
Now, fortunately, technology has come a long way,
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幸运的是,科技已经很发达了
10:01
and we can now grade a range of interesting types of homework.
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我们现在可以批改各种各样的作业
10:05
In addition to multiple choice
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不光是选择题
10:06
and the kinds of short answer questions that you saw in the video,
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还有那种你在视频中看到的简答题
10:09
we can also grade math, mathematical expressions
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我们还可以批改数学或者数学表达式
10:13
as well as mathematical derivations.
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以及数学词源
10:15
We can grade models, whether it's
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我们还可以批改模型,
10:17
financial models in a business class
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不管是在商业课中的金融模型
10:20
or physical models in a science or engineering class
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还是在科学或工程课上的物理模型
10:23
and we can grade some pretty sophisticated programming assignments.
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我们还能批改一些比较复杂的编程作业
10:26
Let me show you one that's actually pretty simple
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让我给大家看一个比较简单的
10:28
but fairly visual.
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不过清晰可见
10:30
This is from Stanford's Computer Science 101 class,
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这是斯坦福的计算机科学101课程
10:32
and the students are supposed to color-correct
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学生应当去更正模糊的
10:34
that blurry red image.
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红色区域
10:35
They're typing their program into the browser,
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他们在浏览器里直接输入自己的程序
10:37
and you can see they didn't get it quite right, Lady Liberty is still seasick.
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你可以看到他们没有弄对,自由女神还没来拯救他们
10:41
And so, the student tries again, and now they got it right, and they're told that,
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于是学生又试了一次,现在他们弄对了,然后他们就被告知
10:45
and they can move on to the next assignment.
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可以移动到下一个题目了
10:48
This ability to interact actively with the material
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这种能够和材料积极互动以及
10:51
and be told when you're right or wrong
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被告知自己正确与否的能力
10:52
is really essential to student learning.
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对于学生学习是至关重要的
10:56
Now, of course we cannot yet grade
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不过,当然我们还无法批改
10:58
the range of work that one needs for all courses.
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所有种类的作业
11:01
Specifically, what's lacking is the kind of critical thinking work
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确切地讲,我们缺少一种批判性思维的工作
11:04
that is so essential in such disciplines
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这种思维在人文类,社会科学,商业和
11:06
as the humanities, the social sciences, business and others.
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其他领域都是极其关键的
11:09
So we tried to convince, for example,
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因此我们尝试去,比如说,
11:12
some of our humanities faculty
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让人文学的教职工相信
11:13
that multiple choice was not such a bad strategy.
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多项选择题不是那么坏的一个策略
11:16
That didn't go over really well.
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不过效果却不是很好
11:18
So we had to come up with a different solution.
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因此我们必须想出另外一个办法
11:21
And the solution we ended up using is peer grading.
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最后的解决方案是学生之间互批
11:24
It turns out that previous studies show,
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之前的研究表明
11:26
like this one by Saddler and Good,
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比如Saddler和Good做的这个研究,
11:28
that peer grading is a surprisingly effective strategy
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同伴互批是一个对于提供可复写成绩的
11:30
for providing reproducible grades.
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十分有效的策略
11:34
It was tried only in small classes,
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这曾经只在小课堂中用过,
11:35
but there it showed, for example,
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不过这它显示了,比如说,
11:37
that these student-assigned grades on the y-axis
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这些学生批改的在Y轴上的分数
11:39
are actually very well correlated
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实际上跟老师批改的
11:41
with the teacher-assigned grade on the x-axis.
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在X轴上的分数较为吻合
11:43
What's even more surprising is that self-grades,
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更惊奇的是,自我批改
11:46
where the students grade their own work critically --
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就是让学生自己给自己批改作业
11:48
so long as you incentivize them properly
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只要你合适地激励他们,
11:50
so they can't give themselves a perfect score --
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确保他们不能随随便便就给自己一个满分-
11:52
are actually even better correlated with the teacher grades.
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甚至跟老师批改的成绩更加吻合
11:55
And so this is an effective strategy
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因此这是一个很有效的策略
11:57
that can be used for grading at scale,
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对于大规模作业批改来说
11:59
and is also a useful learning strategy for the students,
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并且还是个对于学生来说有用的学习策略
12:02
because they actually learn from the experience.
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因为他们实际上从这段经验中学到了东西
12:04
So we now have the largest peer-grading pipeline ever devised,
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因此我们现在就有设计出的最大的同龄人批改线
12:09
where tens of thousands of students
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这当中成千上万的学生
12:11
are grading each other's work,
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在互相批改作业
12:12
and quite successfully, I have to say.
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而且我必须说,这很成功
12:15
But this is not just about students
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不过这不只是学生们
12:18
sitting alone in their living room working through problems.
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在客厅干坐着解决问题
12:21
Around each one of our courses,
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在我们的每一个课程
12:22
a community of students had formed,
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一个团队的学生形成了了
12:25
a global community of people
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一个全球性的社区
12:26
around a shared intellectual endeavor.
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都有一个共同的智力目标
12:29
What you see here is a self-generated map
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你在这里看到一张自动生成的地图
12:32
from students in our Princeton Sociology 101 course,
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显示在普林斯顿社会学101课程的学生
12:35
where they have put themselves on a world map,
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从世界各地而来
12:37
and you can really see the global reach of this kind of effort.
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你看以看到这种努力的全球性延伸
12:40
Students collaborated in these courses in a variety of different ways.
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学生在这些课程中以不同的方式进行合作
12:45
First of all, there was a question and answer forum,
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第一,我们有一个问答平台
12:48
where students would pose questions,
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学生可以提出问题,
12:50
and other students would answer those questions.
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然后其他学生可以回答问题
12:52
And the really amazing thing is,
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最惊奇的是
12:54
because there were so many students,
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因为学生太多了
12:56
it means that even if a student posed a question
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这意味着即使有学生在凌晨3点
12:58
at 3 o'clock in the morning,
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提出一个问题
13:00
somewhere around the world,
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在世界上的某个地方
13:01
there would be somebody who was awake
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总有人会醒着
13:03
and working on the same problem.
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在同一问题上工作
13:05
And so, in many of our courses,
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因此,在许多课程中,
13:07
the median response time for a question
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在问答平台上的回答时间中间值
13:10
on the question and answer forum was 22 minutes.
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只有22分钟
13:13
Which is not a level of service I have ever offered to my Stanford students.
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这比我对我斯坦福学生的服务要好得多
13:18
(Laughter)
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(笑声)
13:19
And you can see from the student testimonials
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你还可以从学生的证明书里看到
13:21
that students actually find
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学生实际上发现
13:23
that because of this large online community,
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因为这个巨大的线上社区
13:25
they got to interact with each other in many ways
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学生其实可以以多种方式进行互动
13:28
that were deeper than they did in the context of the physical classroom.
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这其实比在一个教室里的收获还多
13:32
Students also self-assembled,
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学生们还都“组装”自己
13:34
without any kind of intervention from us,
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我们对此不进行任何干扰
13:36
into small study groups.
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组织形成学习小组
13:38
Some of these were physical study groups
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这里面有些是物理学习小组
13:41
along geographical constraints
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来研究地理条件限制
13:42
and met on a weekly basis to work through problem sets.
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他们每周见面去研究一系列问题
13:45
This is the San Francisco study group,
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这是旧金山学习小组
13:47
but there were ones all over the world.
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不过这些人都来自世界各地
13:49
Others were virtual study groups,
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其他都是实质上的小组
13:51
sometimes along language lines or along cultural lines,
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有时候通过语言和文化来划分
13:54
and on the bottom left there,
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在左下方这里
13:56
you see our multicultural universal study group
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你看以看到我们多文化的学习小组
14:00
where people explicitly wanted to connect
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人们直率地去和有其他文化背景的人
14:01
with people from other cultures.
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主动交流
14:04
There are some tremendous opportunities
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这种框架的构建就带来一些
14:06
to be had from this kind of framework.
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巨大的机会
14:10
The first is that it has the potential of giving us
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首先它拥有带给我们
14:13
a completely unprecedented look
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前所未有的
14:16
into understanding human learning.
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在了解人类学习方面的潜力
14:18
Because the data that we can collect here is unique.
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因为我们这里能收集到的数据是独一无二的
14:22
You can collect every click, every homework submission,
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你可以收集到每一次点击,每一次作业提交
14:26
every forum post from tens of thousands of students.
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每一份来自成千上万学生的论坛帖子
14:30
So you can turn the study of human learning
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因此你可以将人类学习的模式
14:32
from the hypothesis-driven mode
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从理论假设的形式
14:34
to the data-driven mode, a transformation that,
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变为以数据为基础的形式,
14:37
for example, has revolutionized biology.
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这是一种,比方说,已经变革生物科学的转型
14:40
You can use these data to understand fundamental questions
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你可以通过这些数据去了解最基本的问题
14:44
like, what are good learning strategies
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比如说,哪些是好的学习策略
14:45
that are effective versus ones that are not?
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哪些是有效的而哪些是无效的?
14:48
And in the context of particular courses,
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而在特定的几个课程背景中,
14:50
you can ask questions
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你可以问像这样的问题:
14:52
like, what are some of the misconceptions that are more common
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有哪些误解是十分常见的,
14:55
and how do we help students fix them?
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如何需要我们帮助学生去更正它们?
14:57
So here's an example of that,
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这儿有一个例子
14:59
also from Andrew's Machine Learning class.
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同样是从Andrew的机器研究课程来的
15:01
This is a distribution of wrong answers
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这是对于Andrew其中一项作业
15:03
to one of Andrew's assignments.
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所有错误答案的分布
15:05
The answers happen to be pairs of numbers,
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答案都是数对
15:07
so you can draw them on this two-dimensional plot.
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因此你可以在二维图象里画出来
15:09
Each of the little crosses that you see is a different wrong answer.
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每一个你看到的小叉叉就是一个不同的错误答案
15:13
The big cross at the top left
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在左上方的大叉叉
15:15
is where 2,000 students
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指的是有2000个学生
15:17
gave the exact same wrong answer.
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得出了一样的错误答案
15:20
Now, if two students in a class of 100
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现在，如果有两个学生在100人的课堂里
15:22
give the same wrong answer,
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给出了同样的错误答案
15:24
you would never notice.
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你肯定发现不了
15:25
But when 2,000 students give the same wrong answer,
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不过当2000人都给出同样的错误答案
15:28
it's kind of hard to miss.
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就很难看不到了
15:29
So Andrew and his students went in,
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因此Andrew和他的学生
15:32
looked at some of those assignments,
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分析了一些作业
15:33
understood the root cause of the misconception,
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然后找到了误解的根本原因
15:37
and then they produced a targeted error message
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然后他们创建了一条专门针对
15:40
that would be provided to every student
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提供错误答案学生的
15:42
whose answer fell into that bucket,
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特别信息
15:44
which means that students who made that same mistake
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这样一来这些学生
15:46
would now get personalized feedback
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就可以得到一种个性化的回馈
15:48
telling them how to fix their misconception much more effectively.
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告诉他们如何更有效地更正误解
15:53
So this personalization is something that one can then build
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因此这种个性化的东西是通过
15:56
by having the virtue of large numbers.
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利用大规模数据的优势来创建的
16:00
Personalization is perhaps
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个性化估计也是这儿
16:02
one of the biggest opportunities here as well,
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最大的机会之一
16:04
because it provides us with the potential
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因为它提供给我们一种
16:07
of solving a 30-year-old problem.
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解决30年未决的问题的潜力
16:09
Educational researcher Benjamin Bloom, in 1984,
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教育研究家Benjamin Bloom在1984年
16:13
posed what's called the 2 sigma problem,
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提出了叫做2 sigma问题
16:15
which he observed by studying three populations.
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他通过学习三种人群观察到的
16:18
The first is the population that studied in a lecture-based classroom.
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第一是在以授课为基础的课堂中学习的人群
16:22
The second is a population of students that studied
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第二是使用标准的以授课为基础的课堂学习的人群
16:24
using a standard lecture-based classroom,
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第二是使用标准的以授课为基础的课堂学习的人群
16:26
but with a mastery-based approach,
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但是有一个旨在精通的方法
16:28
so the students couldn't move on to the next topic
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因此学生必须熟练掌握前一个话题才能继续学习下一个
16:30
before demonstrating mastery of the previous one.
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因此学生必须熟练掌握前一个话题才能继续学习下一个
16:33
And finally, there was a population of students
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最后一个就是
16:36
that were taught in a one-on-one instruction using a tutor.
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在导师一对一课程中受教育的人群
16:40
The mastery-based population was a full standard deviation,
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旨在精通的人群是完全标准差
16:44
or sigma, in achievement scores better
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或者sigma,他们在成就分数方面
16:46
than the standard lecture-based class,
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比标准的以授课为基础的班要好得多
16:48
and the individual tutoring gives you 2 sigma
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而导师一对一的课程在表现提高方面
16:50
improvement in performance.
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就有2个sigma
16:52
To understand what that means,
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为了了解这意味着什么,
16:54
let's look at the lecture-based classroom,
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让我们看看以授课为基础的课堂吧
16:56
and let's pick the median performance as a threshold.
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我们把中位数当做一个门槛
16:58
So in a lecture-based class,
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因此在以授课为基础的课堂中
17:00
half the students are above that level and half are below.
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是一半对一半
17:04
In the individual tutoring instruction,
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在导师一对一授课中,
17:06
98 percent of the students are going to be above that threshold.
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98%都达到了门槛
17:11
Imagine if we could teach so that 98 percent of our students
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想象一个如果我们教的学生
17:14
would be above average.
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98%都在平均标准之上
17:17
Hence, the 2 sigma problem.
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因此,就有这个2 sigma的问题
17:20
Because we cannot afford, as a society,
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因为我们作为一个社会不可能去给
17:22
to provide every student with an individual human tutor.
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每一个学生都提供一个一对一的导师
17:26
But maybe we can afford to provide each student
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但是我们可以提供给他们每人一台电脑
17:28
with a computer or a smartphone.
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或者一部智能手机
17:30
So the question is, how can we use technology
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因此问题是,我们如何应该使用科技
17:32
to push from the left side of the graph, from the blue curve,
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去推动我们摆脱左边蓝色的图像,
17:35
to the right side with the green curve?
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最后到达右边绿色的图像呢?
17:38
Mastery is easy to achieve using a computer,
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通过电脑来实现精通的目地是很简单的,
17:40
because a computer doesn't get tired
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因为电脑对于放5遍同样的视频来说,
17:42
of showing you the same video five times.
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从来不嫌累
17:45
And it doesn't even get tired of grading the same work multiple times,
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而且多次批改同样的作业也不会累
17:48
we've seen that in many of the examples that I've shown you.
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我们在很多我举的例子当中也看到了
17:51
And even personalization
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而且甚至我们也看到
17:53
is something that we're starting to see the beginnings of,
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个性化的设计在逐渐开始发展
17:55
whether it's via the personalized trajectory through the curriculum
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不管是通过课程中个性化的轨道
17:58
or some of the personalized feedback that we've shown you.
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或是一些我们给大家展示的个性化反馈
18:02
So the goal here is to try and push,
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因此我们的目标是尝试看看
18:04
and see how far we can get towards the green curve.
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我们能够多接近那个绿色的图像
18:08
So, if this is so great, are universities now obsolete?
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好吧,那如果这个这么好,大学是不是过时了?
18:13
Well, Mark Twain certainly thought so.
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嗯,马克吐温显然这么想,
18:16
He said that, "College is a place where a professor's lecture notes
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他说:"大学是一个教授的笔记
18:19
go straight to the students' lecture notes,
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直接成为学生的笔记,
18:20
without passing through the brains of either."
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并且都没有经过两者大脑的地方."
18:23
(Laughter)
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(笑声)
18:27
I beg to differ with Mark Twain, though.
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不过我真不敢与马克吐温苟同
18:29
I think what he was complaining about is not
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我认为他在抱怨的不是大学
18:32
universities but rather the lecture-based format
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而是以授课为基础的课堂模式
18:35
that so many universities spend so much time on.
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因为这些模式在大学太流行了
18:38
So let's go back even further, to Plutarch,
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那让我们在往回看看,回到Plutarch(译者注：希腊历史家)
18:41
who said that, "The mind is not a vessel that needs filling,
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他说:"思想不是一个需要填充的容器,
18:43
but wood that needs igniting."
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而是需要点燃的木头."
18:45
And maybe we should spend less time at universities
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因此或许我们应该在
18:47
filling our students' minds with content
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通过授课填充学生脑袋的大学少花点时间,
18:50
by lecturing at them, and more time igniting their creativity,
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而应当多花些时间点燃他们的创造力
18:54
their imagination and their problem-solving skills
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他们的想象力和解决问题的能力
18:57
by actually talking with them.
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通过积极与他们交流来实现
18:59
So how do we do that?
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那么我们怎么做呢?
19:01
We do that by doing active learning in the classroom.
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我们通过主动的学习来实现
19:04
So there's been many studies, including this one,
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有很多研究表明,包括这个,
19:07
that show that if you use active learning,
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如果你使用积极学习法的话,
19:09
interacting with your students in the classroom,
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就是与你的学生在课堂上互动,
19:11
performance improves on every single metric --
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他们的表现会在每个单位不断提高,
19:14
on attendance, on engagement and on learning
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在出勤,在参与度,在学习方面
19:16
as measured by a standardized test.
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尤其在被一个标准测试衡量的时候
19:18
You can see, for example, that the achievement score
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你可以看到,比如说,成就分数
19:20
almost doubles in this particular experiment.
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在这个实验中几乎都翻倍了
19:23
So maybe this is how we should spend our time at universities.
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或许这就是我们如何应当度过大学时光的办法
19:27
So to summarize, if we could offer a top quality education
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因此总结一下,如果我们能免费向世上的每个人提供高质量的教育
19:32
to everyone around the world for free,
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因此总结一下,如果我们能免费向世上的每个人提供高质量的教育
19:34
what would that do? Three things.
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那么会怎么样了?会是这样:
19:37
First it would establish education as a fundamental human right,
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首先教育变成了人类最基本的权利
19:40
where anyone around the world
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世界上所有有能力和积极性的人
19:41
with the ability and the motivation
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世界上所有有能力和积极性的人
19:43
could get the skills that they need
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都可以得到他们想需要的技能
19:45
to make a better life for themselves,
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为他们自己,他们家人, 他们的社区追求更好的生活
19:47
their families and their communities.
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为他们自己,他们家人, 他们的社区追求更好的生活
19:49
Second, it would enable lifelong learning.
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第二,这会使终生学习成为可能
19:52
It's a shame that for so many people,
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对于很多人,在高中或者大学结束后就再也不学了是惭愧的事
19:53
learning stops when we finish high school or when we finish college.
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对于很多人,在高中或者大学结束后就再也不学了是惭愧的事
19:57
By having this amazing content be available,
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通过这样一个项目
19:59
we would be able to learn something new
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每当我们想要的时候,我们可以学一些新知识
20:02
every time we wanted,
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每当我们想要的时候,我们可以学一些新知识
20:03
whether it's just to expand our minds
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不管是用来拓展我们的思维
20:04
or it's to change our lives.
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还是改变我们的生活
20:06
And finally, this would enable a wave of innovation,
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最后,这个项目会带来一股创新潮
20:10
because amazing talent can be found anywhere.
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因为哪里都能找到惊人的天赋
20:13
Maybe the next Albert Einstein or the next Steve Jobs
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或许下一个爱因斯坦或者乔布斯
20:16
is living somewhere in a remote village in Africa.
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就住在非洲一个偏远的小镇上
20:18
And if we could offer that person an education,
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而且如果我们能为那个人提供一份教育
20:21
they would be able to come up with the next big idea
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他们可能会想出下一个极好的主意
20:23
and make the world a better place for all of us.
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使我们的世界变得更美好
20:26
Thank you very much.
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非常感谢
20:27
(Applause)
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(鼓掌)
ABOUT THE SPEAKER
Daphne Koller - EducatorWith Coursera, Daphne Koller and co-founder Andrew Ng are bringing courses from top colleges online, free, for anyone who wants to take them.
Why you should listen
A 3rd generation Ph.D who is passionate about education, Stanford professor Daphne Koller is excited to be making the college experience available to anyone through her startup, Coursera. With classes from 85 top colleges, Coursera is an innovative model for online learning. While top schools have been putting lectures online for years, Coursera's platform supports the other vital aspect of the classroom: tests and assignments that reinforce learning.
At the Stanford Artificial Intelligence Laboratory, computer scientist Daphne Koller studies how to model large, complicated decisions with lots of uncertainty. (Her research group is called DAGS, which stands for Daphne's Approximate Group of Students.) In 2004, she won a MacArthur Fellowship for her work, which involves, among other things, using Bayesian networks and other techniques to explore biomedical and genetic data sets.
Daphne Koller | Speaker | TED.com