Question

PART 1:

Sampling

How we select our sample will directly influence the external validity of the study. If a sample is representative, then our external validity is stronger. If a sample is non-representative, then our external validity is weaker.

QUESTIONS:

1.

You are interested in looking at the relationship between student-to-teacher ratio and GPA at California 2- and 4-year colleges. You suspect that average GPA is higher at 2-year colleges where student-to-teacher ratio is low, relative to 4-year colleges colleges that have higher student-to-teacher ratios.

You compile a list of all registered students for the 2013-2014 academic year at 2- and 4-year colleges. For each student on your list you flip a coin three times. If you get three heads in a row, that student is selected into your sample. What kind of sampling technique did you employ? SELECT ONE OF THE FOLLOW:

A. cluster sampling

B. multistage sampling

C. convenience sampling

D. simple random sampling

E. stratified random sampling

2.

You are interested in looking at the relationship between student-to-teacher ratio and GPA at California 2- and 4-year colleges. You suspect that average GPA is higher at 2-year colleges where student-to-teacher ratio is low, relative to 4-year colleges colleges that have higher student-to-teacher ratios.

You would like to draw a representative sample, but in previous attempts you ended up with a sample that was entirely from 2-year colleges. You realize that there are far more students at 2-year colleges (1.7 million in 2010) than at 4-year colleges (650,000 in 2010). That means that roughly 72% of the enrolled students were enrolled in 2-year colleges and roughly 28% were enrolled in 4-year colleges.

To select your sample of 1000 students, you compile a list of the names of all the students at 2-year colleges, print each name on a slip of paper and put all the paper slips in a hat. You draw out 720 names. You then compile a list of the names of all the students at 4-year colleges, print each name on a slip of paper and put all the paper slips in a hat. You draw out 280 names.

What sort of sampling technique are you using now? SELECT ONE OF THE FOLLOW:

A. cluster sampling

B. multistage sampling

C. convenience sampling

D. simple random sampling

E. stratified random sampling

F. quota sampling

3.

You are interested in looking at the relationship between student-to-teacher ratio and GPA at California 2- and 4-year colleges. You suspect that average GPA is higher at 2-year colleges where student-to-teacher ratio is low, relative to 4-year colleges colleges that have higher student-to-teacher ratios.

You know that there are far more students at 2-year colleges (1.7 million in 2010) than at 4-year colleges (650,000 in 2010) in California. That means that roughly 72% of the enrolled students were enrolled in 2-year colleges and roughly 28% were enrolled in 4-year colleges.

You really want to accurately gauge the average GPA at each type of college. You want to ensure that you have the same number of participants from each type of college. To select your sample of 1000 students, you compile a list of the names of all the students at 2-year colleges, print each name on a slip of paper and put all the paper slips in a hat. You draw out 500 names. You then compile a list of the names of all the students at 4-year colleges, print each name on a slip of paper and put all the paper slips in a hat. You draw out 500 names.

What sort of sampling technique are you using now? SELECT ONE OF THE FOLLOW:

A. cluster sampling

B. multistage sampling

C. convenience sampling

D. simple random sampling

E. stratified random sampling

F. quota sampling

4.

You are interested in looking at the relationship between student-to-teacher ratio and GPA at California 2- and 4-year colleges. You suspect that average GPA is higher at 2-year colleges where student-to-teacher ratio is low, relative to 4-year colleges colleges that have higher student-to-teacher ratios.

You work with your campus chapter of the National Honor Society in Psychology (PsiChi) to obtain a list of all their members at the other 2- and 4-year colleges in California. You email out to all those members and ask them to interview 5 students on their campus. You suggest that they don't just interview their friends, but ask people walking around campus. Each of your new research assistants reports back the type of college (2- or 4-year) and the GPA of the 5 participants they recruited. You are very pleased that thousands of students gathered data.

What sort of sampling technique have you used? SELECT ONE OF THE FOLLOW:

A. cluster sampling

B. multistage sampling

C. convenience sampling

D. simple random sampling

E. stratified random sampling

F. quota sampling

PART 2:

Population

The population of interest to a researcher is comprised of all of the individuals who share a group of characteristics. Researcher may define their population as very broad (e.g., "Human Beings") or very narrow (e.g., "Students currently enrolled in PSC126").

QUESTIONS:

1.

You are a researcher interested in the factors that affect grade point average (GPA) in California colleges. What is your population of interest? SELECT ONE OF THE FOLLOW:

A. all university of california students

B. all college students in the united states

C. all UCF students

D. all college students in california

PART 3:

Identify the best label for the outcome/dependent variable:

QUESTION:
Claim: Gamers don't play as hard if avatar is overweight. SELECT ONE OF THE FOLLOW:

A. pay as hard

B. avatar body type

C. play effort

D. overweight

PART 4:

Actual Population

We need to very carefully consider our population of interest and our sampling technique. Sometimes in research, the population that we end up drawing our sample from is subtly different from the entire population we are interested in.

QUESTIONS:

1.

A researcher is interested in the types of injuries that occur at a skate park. She sets up a hidden camera at a skate park and watches for people who are injured. Her population of interest is "injuries that occur at a skate park".

What is the population from which her sample was actually drawn? SELECT ONE OF THE FOLLOW:

A. all injuries

B. injuries that occur at a skate park that were serious enough to result in a doctors visit

C. injuries that occur at a skate park

2.

A researcher is interested in attitudes of UC Davis students. He stands outside the MU and recruits participants as they walk past. His population of interest is "UC Davis students".

What is the population from which his sample was actually drawn? SELECT ONE OF THE FOLLOW:

A. uc davis students who walk past the MU that day

B. uc davis students who are on campus that day

3.

A researcher is interested in the attitudes of enrolled UCDavis students. She asks the registrar for a list of enrolled students. Her population of interest is "enrolled UCDavis students".  

What is the population from which her sample was actually drawn? SELECT ONE OF THE FOLLOW:

A. enrolled ucdavis students

B. american college students

C. enrolled ucdavis students who were on campus that day

C. uc davis students

Answer 1

Answer

• PART I

1. The correct answer is - D

A simple random sampling is the sort of sampling technique that I am using or employed in this case.

2. The correct answer is - E

A Stratified random sample is the sort of sampling technique that I am using or employed in this case.

3. The correct answer is - F

Quota sampling is the sort of sampling technique that I am using or employed in this case.

4. The correct answer is - C

Convenience sampling is the sort of sampling technique that I am using or employed in this case.