Daphne Koller: What we're learning from online education

668,704 views ・ 2012-08-01

TED


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00:00
Translator: Morton Bast Reviewer: Thu-Huong Ha
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翻译人员: Yuguo Zhang 校对人员: Charles LI
00:15
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
00:22
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
00:26
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
00:30
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
00:34
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,
00:45
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
00:53
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
00:56
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
01:00
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
01:04
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,
01:08
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,
01:13
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
01:17
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
01:21
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
01:27
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
01:29
trying to get her son a chance at a better life.
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的机会
01:33
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
01:36
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
01:43
about the rising cost of health care.
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医疗保险的价格上升
01:45
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
01:48
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
01:52
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%
01:59
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
02:03
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,
02:07
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
02:10
Only a little over half of recent college graduates
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只有仅仅过半的在美国
02:13
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
02:15
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
02:25
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
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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
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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
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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
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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
02:48
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
02:51
three big Stanford classes,
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所展示了
02:53
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
02:57
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
03:00
the Machine Learning class offered by my colleague
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由我一个同事和Andrew Ng教授
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and cofounder Andrew Ng.
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共同创办的机器研究课程
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Andrew teaches one of the bigger Stanford classes.
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Andrew是教授斯坦福的大课程的
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It's a Machine Learning class,
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是机器研究课程
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and it has 400 people enrolled every time it's offered.
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每回都有400多人参加
03:11
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,
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it had 100,000 people registered.
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100000人注册了
03:17
So to put that number in perspective,
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就这样来说吧,
03:19
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
03:21
by teaching a Stanford class,
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影响到那么多人
03:23
he would have to do that for 250 years.
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他得用250年时间
03:27
Of course, he'd get really bored.
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当然,他肯定会无聊死
03:30
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
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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
03:36
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
03:40
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)
03:42
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
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from the best instructors at the best universities
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中学到最好的课程
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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
03:52
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
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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
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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
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of what that looks like.
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大概是什么样子吧
04:03
(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
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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
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We get unbelievable segregation.
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我们有不可置信的种族分离
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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,
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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
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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
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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
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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
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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
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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
04:34
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
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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....
04:41
(Applause)
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(鼓掌)
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DK: It turns out, maybe not surprisingly,
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DK: 结果呢,可能不是很令人吃惊,
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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
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from the best universities for free.
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最好的课程内容
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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
05:01
We have 1.5 million enrollments,
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我们有150万次的申请
05:03
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
05:06
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
05:11
But it's not just about the numbers,
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不过这不仅跟数字有关
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it's also about the people.
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还跟人有关
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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
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and would never have access in this case
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绝不会得到斯坦福水准的
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to a Stanford-quality course
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课程,而且也无法支付那些课程的
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and would never be able to afford it.
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Akash
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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
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and wants to hone her skills
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想在家里学点技能
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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
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Or Ryan, who can't go to school,
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还是Ryan, 他不能上学
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because his immune deficient daughter
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因为他的无抵抗力的女儿
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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
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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--
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recently, we've been in correspondence with Ryan --
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最近,我们在与Ryan联系
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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
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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
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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
05:55
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?
05:57
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
06:01
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
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It started on a given day,
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从固定的一天开始,
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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
06:10
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
06:17
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
06:19
These are the spikes showing
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这些顶端表明
06:21
that procrastination is global phenomenon.
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耽搁是一个全球现象
06:25
(Laughter)
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(笑声)
06:27
At the end of the course,
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在每门课结束后
06:29
the students got a certificate.
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学生们会得到一个证书
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They could present that certificate
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他们可以把证书给雇主看
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to a prospective employer and get a better job,
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然后得到一个更好的工作
06:35
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
06:37
Some students took their certificate
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很多学生拿着证书
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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
06:42
for actual college credit.
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索要真正的大学学分
06:44
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
06:46
for their investment of time and effort.
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的确在得到一些有意义的东西
06:49
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
06:56
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
07:01
you can break away from, for example,
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你可以不再使用,比如说
07:04
the monolithic one-hour lecture.
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单调的一小时讲座的模式
07:06
You can break up the material, for example,
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你可以将材料,比如说,
07:08
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
07:17
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
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So, for example, some students might benefit
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比如说,一些学生会从
07:23
from a little bit of preparatory material
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一点点的准备材料中收益
07:26
that other students might already have.
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但其他学生可能已经了解了
07:28
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
07:37
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,
07:46
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.
07:49
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
07:52
is that we need to have students
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是需要让这些学生通过
07:55
who practice with the material
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材料的练习去
07:57
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,
08:06
demonstrates that even simple retrieval practice,
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表明了即使是简单的重复小练习
08:09
where students are just supposed to repeat
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只需要学生重复
08:12
what they already learned
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他们刚刚学到的东西
08:13
gives considerably improved results
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会带来很大的提高效果
08:15
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
08:22
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
08:27
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
08:31
Every few minutes, the video pauses
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每过几分钟,视频就会暂停下来
08:33
and the students get asked a question.
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然后学生必须回答一个问题
08:35
(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
08:45
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
08:47
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
08:56
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
08:58
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
09:04
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
09:06
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,
09:09
80 percent of the students
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80%的学生
09:10
are still scribbling the last thing I said,
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还在琢磨我前面说的话
09:12
15 percent are zoned out on Facebook,
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15%的学生都沉浸在Facebook里,
09:15
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
09:18
who blurts out the answer
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直接在其他人还没机会思考的之前
09:19
before anyone else has had a chance to think about it,
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一口报出正确答案.
09:21
and I as the instructor am terribly gratified
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然后作为老师我极度满足
09:24
that somebody actually knew the answer.
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竟然有人知道答案
09:26
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...
09:32
Here, every single student
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在这,每个学生
09:35
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
09:41
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
09:44
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
09:48
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,
09:51
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?
09:54
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
09:58
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
10:04
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
10:12
as well as mathematical derivations.
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以及数学词源
10:14
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
10:19
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
10:22
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
10:29
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
10:33
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
10:47
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
10:50
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
10:55
Now, of course we cannot yet grade
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不过,当然我们还无法批改
10:57
the range of work that one needs for all courses.
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所有种类的作业
11:00
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
11:03
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
11:05
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,
11:11
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
11:15
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
11:20
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
11:23
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,
11:27
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
11:33
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,
11:36
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
11:40
with the teacher-assigned grade on the x-axis.
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在X轴上的分数较为吻合
11:42
What's even more surprising is that self-grades,
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更惊奇的是,自我批改
11:45
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,
11:49
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-
11:51
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
11:56
that can be used for grading at scale,
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对于大规模作业批改来说
11:58
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
12:01
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
12:03
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
12:08
where tens of thousands of students
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这当中成千上万的学生
12:10
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
12:17
sitting alone in their living room working through problems.
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在客厅干坐着解决问题
12:20
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
12:24
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
12:28
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
12:31
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
12:34
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
12:44
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
12:47
where students would pose questions,
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学生可以提出问题,
12:49
and other students would answer those questions.
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然后其他学生可以回答问题
12:51
And the really amazing thing is,
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最惊奇的是
12:53
because there were so many students,
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因为学生太多了
12:55
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
12:57
at 3 o'clock in the morning,
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提出一个问题
12:59
somewhere around the world,
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在世界上的某个地方
13:00
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
13:09
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
13:17
(Laughter)
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(笑声)
13:18
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
13:20
that students actually find
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学生实际上发现
13:22
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
13:27
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
13:31
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
13:40
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
13:44
This is the San Francisco study group,
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这是旧金山学习小组
13:46
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
13:55
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
13:59
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
14:09
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
14:15
into understanding human learning.
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在了解人类学习方面的潜力
14:17
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
14:21
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
14:25
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
14:29
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,
14:36
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
14:43
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:
14:51
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
14:58
also from Andrew's Machine Learning class.
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2016
同样是从Andrew的机器研究课程来的
15:00
This is a distribution of wrong answers
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这是对于Andrew其中一项作业
15:02
to one of Andrew's assignments.
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所有错误答案的分布
15:04
The answers happen to be pairs of numbers,
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答案都是数对
15:06
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
15:08
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
15:12
The big cross at the top left
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在左上方的大叉叉
15:14
is where 2,000 students
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指的是有2000个学生
15:16
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
15:23
you would never notice.
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你肯定发现不了
15:24
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
15:27
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
15:31
looked at some of those assignments,
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分析了一些作业
15:32
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
15:39
that would be provided to every student
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提供错误答案学生的
15:41
whose answer fell into that bucket,
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特别信息
15:43
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
15:52
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
15:59
Personalization is perhaps
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个性化估计也是这儿
16:01
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
16:06
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
16:12
posed what's called the 2 sigma problem,
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提出了叫做2 sigma问题
16:14
which he observed by studying three populations.
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他通过学习三种人群观察到的
16:17
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
16:21
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
16:25
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
16:29
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
16:35
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
16:43
or sigma, in achievement scores better
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或者sigma,他们在成就分数方面
16:45
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,
16:53
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
16:55
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
16:59
half the students are above that level and half are below.
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是一半对一半
17:03
In the individual tutoring instruction,
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在导师一对一授课中,
17:05
98 percent of the students are going to be above that threshold.
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98%都达到了门槛
17:10
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
17:16
Hence, the 2 sigma problem.
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因此,就有这个2 sigma的问题
17:19
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
17:25
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
17:27
with a computer or a smartphone.
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或者一部智能手机
17:29
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
17:31
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?
17:37
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,
17:41
of showing you the same video five times.
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从来不嫌累
17:44
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
17:52
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
18:01
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
18:07
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?
18:12
Well, Mark Twain certainly thought so.
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嗯,马克吐温显然这么想,
18:15
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
18:18
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."
18:22
(Laughter)
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(笑声)
18:26
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
18:31
universities but rather the lecture-based format
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而是以授课为基础的课堂模式
18:34
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
18:37
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)
18:40
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,
18:42
but wood that needs igniting."
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2023
而是需要点燃的木头."
18:44
And maybe we should spend less time at universities
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2190
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,
18:49
by lecturing at them, and more time igniting their creativity,
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3800
而应当多花些时间点燃他们的创造力
18:53
their imagination and their problem-solving skills
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3255
他们的想象力和解决问题的能力
18:56
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?
19:00
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
19:03
So there's been many studies, including this one,
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有很多研究表明,包括这个,
19:06
that show that if you use active learning,
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如果你使用积极学习法的话,
19:08
interacting with your students in the classroom,
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就是与你的学生在课堂上互动,
19:10
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,
19:13
on attendance, on engagement and on learning
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2449
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
19:19
almost doubles in this particular experiment.
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在这个实验中几乎都翻倍了
19:22
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
19:31
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
19:33
what would that do? Three things.
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那么会怎么样了?会是这样:
19:36
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
19:39
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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1921
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
19:46
their families and their communities.
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2017
为他们自己,他们家人, 他们的社区追求更好的生活
19:48
Second, it would enable lifelong learning.
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第二,这会使终生学习成为可能
19:51
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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3312
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
19:56
By having this amazing content be available,
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2481
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
20:01
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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1329
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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1959
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
20:09
because amazing talent can be found anywhere.
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因为哪里都能找到惊人的天赋
20:12
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
20:15
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
20:20
they would be able to come up with the next big idea
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2356
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
20:25
Thank you very much.
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非常感谢
20:26
(Applause)
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7583
(鼓掌)
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