0:00:00.060,0:00:03.464
- [Yan Chen] It's good that we have[br]an army of enthusiasts

0:00:03.464,0:00:05.390
writing Wikipedia articles,

0:00:05.960,0:00:10.868
but sometimes when it concerns [br]a disease that I might have,

0:00:10.877,0:00:13.494
I really want the experts' input.

0:00:13.790,0:00:15.574
♪ [music] ♪

0:00:26.647,0:00:30.240
Wikipedia is one of the most [br]important references

0:00:30.240,0:00:31.932
for the general public

0:00:31.991,0:00:36.818
It's actually one of the top five[br]most visited websites in the world.

0:00:37.051,0:00:40.900
Everyone reads Wikipedia articles,[br]but sometimes you spot an error

0:00:40.900,0:00:44.101
or you say, [br]"Well, this is not really correct."

0:00:44.101,0:00:45.418
But you move on

0:00:45.418,0:00:48.219
and say, "Someone else might fix it."

0:00:51.108,0:00:53.694
That's called the "free rider problem."

0:00:55.131,0:00:58.702
The success of Wikipedia [br]has been really surprising

0:00:58.702,0:01:03.069
for economists because it relies [br]purely on volunteer labor.

0:01:03.437,0:01:07.969
The medical profession has found[br]that patients tend to bring printouts

0:01:07.969,0:01:10.785
of Wikipedia articles [br]to their doctor's office.

0:01:11.515,0:01:14.223
Some of these articles [br]are of low quality

0:01:14.224,0:01:16.528
because they were not written by experts.

0:01:16.528,0:01:21.411
We're trying to figure out [br]what are the some of the motivators

0:01:21.411,0:01:24.800
to get experts to contribute [br]to high quality content.

0:01:25.064,0:01:28.832
So we decided to do a field experiment[br]to tease out the causalities,

0:01:28.832,0:01:32.332
to figure out what motivates people[br]to contribute to Wikipedia,

0:01:32.332,0:01:34.927
whether it's social impact [br]or private benefit

0:01:34.927,0:01:39.081
or public acknowledgement,[br]or a combination of these factors.

0:01:42.286,0:01:44.603
So in this study,[br]in this field experiment,

0:01:44.603,0:01:47.970
we contacted about 4,000[br]academic economists.

0:01:47.970,0:01:49.439
We have a generic message

0:01:49.439,0:01:52.805
which says Wikipedia [br]is a very valuable public good,

0:01:52.805,0:01:57.620
and yet lots of the articles [br]are inaccurate or not up to date.

0:01:57.620,0:02:01.089
Would you spend [br]10 to 15 minutes commenting

0:02:01.089,0:02:02.871
on these Wikipedia articles?

0:02:02.871,0:02:06.205
Then we vary the paragraphs [br]depending on whether

0:02:06.205,0:02:08.322
they're in the treatment [br]or the control group.

0:02:08.861,0:02:12.061
In the control group, [br]we don't mention that the articles

0:02:12.061,0:02:13.885
might cite your research.

0:02:14.838,0:02:19.129
And in the private benefit condition [br]we say they might cite your research,

0:02:19.129,0:02:21.962
and we have another condition[br]which says, "We will publicly

0:02:21.962,0:02:24.607
acknowledge your contributions."

0:02:27.153,0:02:30.706
Simply asking the expert,[br]"Would you contribute?"

0:02:30.837,0:02:33.938
you get a pretty high response rate,

0:02:34.027,0:02:37.662
which is about 45% of the people[br]say, "Yes, I'm willing."

0:02:37.662,0:02:41.510
When we sent out the links,[br]it turns out a third of the people

0:02:41.510,0:02:45.532
actually contributed,[br]and we look at what are the features

0:02:45.532,0:02:47.525
that predict contributions.

0:02:48.011,0:02:53.450
It turns out that if the article is [br]really well-matched

0:02:53.720,0:02:55.866
to their research expertise,

0:02:56.107,0:02:58.506
they're much more likely [br]to contribute,

0:02:58.587,0:03:00.887
and they're contributing [br]higher quality content.

0:03:01.371,0:03:04.629
So good matching is really [br]important for volunteering.

0:03:04.945,0:03:08.646
We also try to figure out[br]are people more motivated

0:03:08.646,0:03:12.194
by the private benefits,[br]what they get out

0:03:12.194,0:03:13.946
of the contributions.

0:03:13.946,0:03:16.695
So we do that by telling [br]the treatment group

0:03:16.695,0:03:19.710
that we'll send you articles[br]to comment on

0:03:19.710,0:03:21.578
that might reference your research.

0:03:21.578,0:03:25.984
So it turns out that knowing[br]that you might be cited

0:03:25.984,0:03:30.894
increases the positive response rate[br]by about 13%.

0:03:31.594,0:03:35.195
We also find [br]that the public acknowledgement,

0:03:35.195,0:03:37.962
saying that we will post [br]your contributions

0:03:37.962,0:03:40.923
and acknowledge [br]your contributions publicly,

0:03:40.923,0:03:44.794
people are more likely [br]to provide high quality content.

0:03:46.011,0:03:50.095
And public impact --[br]you know we vary the views

0:03:50.095,0:03:52.861
of the Wikipedia articles[br]that we sent.

0:03:52.861,0:03:57.444
We either say on average,[br]a Wikipedia will get 426 views.

0:03:57.444,0:04:01.934
But we'll send articles which have [br]at least 1,000 views to you.

0:04:01.934,0:04:07.623
People are most motivated[br]when the private benefit

0:04:07.623,0:04:09.773
is combined with the social impact.

0:04:09.773,0:04:12.745
The social impact [br]by itself actually doesn't

0:04:12.745,0:04:14.706
quite have the same effect.

0:04:18.923,0:04:21.790
I think if we replicate it [br]in other fields

0:04:21.790,0:04:24.831
we'll have more confidence[br]that private benefits,

0:04:24.831,0:04:28.474
such as citation benefits,[br]would get people interested

0:04:28.474,0:04:31.219
in contributing, [br]and citation benefits

0:04:31.219,0:04:33.102
in combination [br]with social impact

0:04:33.102,0:04:35.502
would have a larger effect.

0:04:35.604,0:04:38.653
We need to push it [br]to other fields as well

0:04:38.653,0:04:42.621
to see if they're robust[br]across different communities.

0:04:43.270,0:04:45.388
- [Narrator] Want to see more[br]economists in the wild?

0:04:45.388,0:04:46.760
Check out our playlist.

0:04:46.760,0:04:47.843
Are you a teacher?

0:04:47.843,0:04:49.877
Here's some related material [br]for your classroom.

0:04:49.877,0:04:51.225
Want to dive deeper?

0:04:51.225,0:04:54.377
Wikipedia is what economists [br]call a "public good."

0:04:54.377,0:04:56.278
Learn more by watching this video.

0:04:56.698,0:04:58.231
♪ [music] ♪