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Chapter 7: Problem 28

Suppose you attend a school that offers both traditional courses and online courses. You want to know the average age of all the students. You walk around campus asking those students that you meet how old they are. Would this result in an unbiased sample?

Short Answer

Expert verified
No, the sample would be biased. It only includes the ages of students who are on campus at that time and willing to answer the question, potentially excluding online students and other students not on campus at that time.

Step by step solution

01

Understanding the definition of an Unbiased Sample

It's important to understand that in the context of statistics, an unbiased sample is a set of observations chosen randomly without any favor or prejudice, giving it high representativeness of the overall population. Each member of the population should have an equally likely chance to be part of the sample.
02

Evaluating the given Scenario

Now let's evaluate this case. In the scenario where you walk around campus asking students about their ages, it's clear that the method of selecting the sample is not random. It's confined to students who are available on the campus at that time and who are willing to participate in the survey.
03

Determining if the Sample is Biased or Unbiased

Given that online students and possibly some traditional courses students who aren't on the campus at that time aren't included, it's evident that there's a bias in the sample selection. Thus, the sample obtained through this method wouldn't be an unbiased sample.

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