Concept explainers
(a)
Identify the selection bias in the study of heart disease and fast food.
(a)
Explanation of Solution
In the study of 5,000 office workers in Chicago, they considered only two variables such as heart diseases and fast food. But, in reality there were many reasons behind the heart diseases of a person. For example, lack of exercise, or a poor healthy life style and so on. With these reasons, there is also a possibility of regularly dine on fast food. Therefore, eating fast food thrice or many times per week is not only the reason for heart disease. Therefore, selection bias occurs in this study.
Selection bias: A selection bias occurs in a study, if the sample used in that study is not random.
(b)
Identify the selection bias in the study of senior assisted living facilities.
(b)
Explanation of Solution
A survey of senior-assisted living facilities states that majority of residents are females. Because, on an average, female tend to outlive men. But, this is not in the case of old men citizens. They do not need much assistance as older women. But, the notable fact that there are several older women in the population than older men. Therefore, selection bias occurs in this study.
Selection bias: A selection bias occurs in a study, if the sample used in that study is not random.
(c)
Identify the selection bias in the study of graduation from private and public universities.
(c)
Explanation of Solution
This study of college students' graduation from private and public universities states that an education from private university will enhance students' earnings. Those who have selected private university have more earning potential than those who have selected public universities. Therefore, private university is more selective. In other words, those students who have greater earning potential would likely select private universities.
Selection bias: A selection bias occurs in a study, if the sample used in that study is not random.
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Chapter 22 Solutions
Principles of Microeconomics, Student Value Edition Plus MyLab Economics with Pearson eText -- Access Card Package (12th Edition)
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