Question

Determine whether the sample is biased or unbiased. Explain how you know. If the sample is biased, give an example of an unbiased sample for the situation. You want to estimate the number of students in your school who play a musical instrument. You survey the first 15 students who arrive at a band class.

Answer 1

Answer: This is a biased sample.

Explanation:

A biased sample is when there is some kind of "selection" in your sampling process, where in order to avoid this we should have the most random selection that we can make

Here, the sample is "the first 15 students who arrive at a band class"

Here is obviously a bias, because you could think that these students may be more "dedicated" students than the ones that will arrive later to the class, and we also have the fact that all the students in our sample are in the same class, so there is another bias.

Then we can conclude that this is a biased sample.