Question

1. Suppose you want to survey the opinions of the residents of an apartment complex. The complex contains 100 buildings, each with 8 units per building, for a total of 800 units. You decide to sample 160 of the units. Suppose you randomly sample 20 buildings, and then select every unit in those 20 buildings to be in your sample, for a total of 160 units. What sampling method did you use?

	1.	A systematic sample.
	2.	A stratified sample.
	3.	A cluster sample.
	4.	A simple random sample

2. Which of the following studies can result in researchers extending the results inappropriately because the sample doesn’t represent the intended population?

	1.	Studies involving randomly selected participants
	2.	Studies involving convenience samples
	3.	Experimental studies
	4.	All of the above

3. Suppose a survey was conducted to find out what proportion of Americans intend to vote in the next Presidential election. For which of the following confidence intervals would it be fair to conclude, with high confidence, that a majority of Americans will vote in the next Presidential election?

		55% plus or minus 13%
		55% plus or minus 6%
		53% plus or minus 1%
		All of the above are too close to call.

4. Making a type II error is only possible if ____ is true.

		The p-value.
		the null
		The alternative
		None of the above.

Answer 1

1.

Cluster sampling is dividing the population into separate groups, called clusters. Then, a simple random sample of clusters is selected from the population.

Here, the same thing has been done.

Option C is the right answer.

2.

A convenience sample is a type of non-probability sampling method where the sample is taken from a group of people easy to contact or to reach.

Here, studying involving convenience sampling can only cause inappropriate results.

Option B is the right answer.

3.

55% plus or minus 13% is the largest interval we do have here, which is from 42 to 68%.

Hence, Option A is the right answer.

4.

A Type ll error is when you accept a false null hypothesis. It means that the alternate hypothesis is correct in the case of Type II error.

Option C is the right answer.