00:01
All right, so for part a here, regarding the sampling size, we can see that the sample size, n equals 25, is very small.
00:20
There's not really a whole lot to say about the fact that this sampling size is small, but there is more interesting, there are more interesting things to say about the sampling method.
00:31
So regarding the method, the first problem is that the, that the, that, the, that, the, they ask students to volunteer.
00:47
That is going to be introducing a kind of selection bias.
00:50
Only a particular type of person would volunteer to do a survey.
00:54
The second problem with the method is the fact that the teacher is present.
01:04
The teacher, whom the survey is about, is present.
01:09
So that is likely going to be biasing the results that the students give in the survey because they're probably not going to want the teacher to see what they actually think if they have a negative opinion.
01:21
Now, for part b, one advantage of using the survey method is the fact that it is typically cheap and easy.
01:40
The disadvantage would be that it is very susceptible to bias, or specifically susceptible to selection bias, or response bias.
02:22
For part c, this is sort of one, what i was saying back in part a, but the fact that the teacher is present, the teacher's presence will effectively, saying intimidate might be a little bit of an extreme way to put it, but effectively that is the idea.
02:53
The teacher's presence will intimidate students into more positive results or more positive answers.
03:11
Or even if it's not a matter of intimidation, we'd have that students may not want to hurt, may not want to hurt the teacher's feelings...