OFFICIAL44 Why does the professor mention lighting?

[00:00.00]NARRATOR: Listen to a conversation between a student and her sociology professor.
[00:06.71]MALE PROFESSOR: I'm glad you got my message and were able to make it … [00:09.35]but where are the other members of your group, [00:11.76]Tom and Jane?
[00:13.08]FEMALE STUDENT: They're actually at the library …. [00:15.05]They have a biology lab assignment that's due later this afternoon … [00:18.98]so I'm here to represent the whole group.
[00:21.51]But, um, when we got your e-mail message—about being worried about our research project—we were a little confused. We thought you were excited about our idea for the project ….
[00:33.00]MALE PROFESSOR: Well, I think it's a great research topic, but when I looked closely at your plan for accomplishing the research, I realized that your group was probably asking for some trouble.
[00:42.63]FEMALE STUDENT: What do you mean? [00:43.83]I thought that … you know … by monitoring students studying in the library, we could really, uh, get a good understanding of people’s study habits and stuff.
[00:54.24]MALE PROFESSOR: The thing is … I think you might have a problem because of the Hawthorne effect.
[00:59.18]FEMALE STUDENT: The Hawthorne effect?
[01:01.80]MALE PROFESSOR: The Hawthorne effect is a technical term for when researchers … uh, more or less forget about a specific variable … the variable of the researchers themselves.
[01:13.87]Now, the students in the library … they're going to know that you’re observing them, right? [01:19.60] So you have to consider the effect your very presence will have on the people you’re observing.
[01:24.84]FEMALE STUDENT: But … so you think … [01:27.52]I-I mean, it's not like our observations would be a secret ….  [01:31.77]The students would know exactly what we'd be doing ….  [01:34.77]I mean, we'd put up a sign right outside the library ….
[01:38.79]MALE PROFESSOR: Yes … but that’s just it …. [01:41.50]When people know they're being watched, they act differently. [01:45.90]Let me explain how the Hawthorne effect got its name and … well, you'll get the idea.
[01:51.77]See, there was a manufacturing facility called the Hawthorne plant. [01:56.41]And researchers conducted some experiments there to see what conditions made workers the most productive.
[02:02.12]FEMALE STUDENT: What sort of conditions?
[02:03.71]MALE PROFESSOR: Well … one thing they experimented with was the lights …. [02:07.92]Were workers more productive with bright lights or dim lights? [02:11.58]Well, here’s the thing: Whatever the researchers did, the workers’ productivity increased. [02:18.07]When the lighting was improved, productivity went up. [02:21.33]When the lighting was dimmed, productivity went up again.
[02:25.21]FEMALE STUDENT: That doesn't make a lot of sense.
[02:26.89]MALE PROFESSOR: Exactly…. So initially, the experiment was considered a failure. [02:32.09]But then the researchers realized that their own presence had affected the workers'productivity.[02:38.90] The workers knew that the researchers were watching them, and with so much attention on them, the workers felt compelled to work harder.
[02:46.84]FEMALE STUDENT: Oh … I guess that really could be an issue with my group's research.
[02:51.91]MALE PROFESSOR: Yes…. But I don't want to send you all back to square one … [02:55.42]so how about you set up a meeting with your group members and discuss this. [03:00.26]Then we can meet again and go over your ideas … [03:03.51]and I think that we should be able to figure out a way to get around the problem.