Question

Answer the two questions below

3. Suppose that you are going to select a random sample of students from your school, measure the heights of the students in your sample, and then find the mean height for your sample. There are many different sets of students who could end up forming your sample. Will the sample mean be the same for all possible samples? If so, explain why. If not, what is the phrase used for the fact the sample means will vary according to the sample selected?

4. Return to the context of the previous item. The sample mean will vary according to what sample you happen to select. If you want to reduce this variation, would you choose to select a sample of size 5 or a sample of size 25?

Answer 1

3: No

4: 25

Explanation:

3: It won't because not everyone is the same height and there will be variation in the mean height.

4: A larger sample size will give a more accurate representation of the population, where as a sample size of 5 is much more likely to have a higher percentage of outliers, and each outlier matters much more in finding the mean. In a sample size of 25, each outlier matters much less.