Question

 

Research question: Amongst Penn State World Campus students, do those who sleep more tend to have higher grade point averages (GPAs)?

Researchers are going to collect data from a sample of 100 Penn State World Campus students. They will call each student to ask how many hours they slept last night and they will ask each student for their GPA (scale of 0 to 4.0).

7. Describe how researchers could use a convenience sampling method to obtain a sample of 100 World Campus students. In other words, describe the procedures of obtaining a convenience sample in this scenario.

8. Describe how researchers could use a simple random sampling method to obtain a sample of 100 World Campus students. In other words, describe the procedures of obtaining a simple random sample in this scenario.

9. In order to obtain a sample that is representative of the intended population, should researchers use the convenience sampling method from question 7 or the simple random sampling method from question 8?

10. Using this scenario, describe an example of response bias. Response bias would occur in this study if… 1

1. Using this scenario, describe an example of non-response bias. Non-response bias would occur in this study if…

12. If a positive relationship is observed between hours of sleep and GPA, can the researchers conclude that sleeping longer causes higher GPAs? Explain why or why not.

13. What is one possible confounding variable in this study? Explain why this is a possible confounding variable.

Answer 1

7. The researchers can just go to any Central Place like Library, Canteen etc., where the students generally go and interview the first 100 students they meet. In this way, the researchers could use a convenience sampling method to obtain a sample of 100 World Campus students.

8. From the records available with the management of Penn State World Campus, the researchers must make a list of all the students giving roll numbers starting from 1 to each and every students. Then, using Random Number Generator of a Computer, they can get 100 random numbers. The students with these 100 random numbers as their roll numbers constitute the required simple random sample in this scenario.

9. In order to obtain a sample that is representative of the intended population, the researchers should the simple random sampling method from question 8 because it it statistically very reliable representative of the whole population of Penn State World Campus students.

10. Response bias is the tendency of a person to answer questions on a survey untruthfully due to socially acceptability. Response bias would occur in this study if a particular student has GPA very low and the interview is open,the student will tell his GPA high falsely.

11. Non-response bias occurs when some respondents included in the sample do not respond. Non-response bias would occur in this study if the survey questionnaire is very long and answering is cumbersome so that many students will just ignore them because there is no compulsion or incentive for answering.

12. If a positive relationship is observed between hours of sleep and GPA, the researchers cannot conclude that sleeping longer causes higher GPAs because a third Confounding Variable may be present which affects both the variables: hours of sleep and GPA and in reality, both the variables: hours of sleep and GPA may not be related at all.

13. One possible confounding variable in this study is the easiness or toughness of the subject of the study of the student. If the subject is very tough,the student will get low GPA irrespective of his sleep. If the subject is very easy,the student will get high GPA irrespective of his sleep.