Question

A university wants to study the experience of students enrolled in its big classes, defined asclasses with enrollments of 500 or more. There are 20 such classes. From each of these classes,one enrolled student is chosen uniformly at random to take part in the university’s survey. Youcan assume that the selection from each class is performed independently of the selections inthe other classes. In this scenario: (T / F)

1. The method of sampling produces a probability sample of students enrolled in the big classes. (T / F)

2. The method of sampling produces a simple random sample of students enrolled in the big classes. (T / F)

3. Because a student is chosen from each class, all students in the big classes have the same chance of being selected. (T / F)

4. Because a student is chosen from each of 20 big classes, there will be 20 students in the sample. (T / F)

Answer 1

1. The method of sampling produces a probability sample of students enrolled in the big classes.

Correct option:

T

Explanation:
This is true because in this case the sample from a large population is chosen using a method based on theory of probability.

2. The method of sampling produces a simple random sample of students enrolled in the big classes.

Correct option:

F

Explanation:

This is false because Stratified Sampling Technique is adopted here to ensure the representation of of the 20 classes.But it is not Simple Random Sampling (SRS) because the probability of election of each student is not the same as the probability of selection of each student depends on the strength of his class.

3. Because a student is chosen from each class, all students in the big classes have the same chance of being selected.

Correct option:

F

Explanation:

This is false because the probability of election of each student is not the same as the probability of selection of each student depends on the strength of his class.

4. Because a student is chosen from each of 20 big classes, there will be 20 students in the sample.

Correct option:

T

Explanation:
This true because there are 20 classes. From each class we are selecting 1 student. So, total number of students selected is 20.