1. A political party sends a mail survey to 1500 randomly selected registered vo
ID: 3327205 • Letter: 1
Question
1. A political party sends a mail survey to 1500 randomly selected registered voters in a community. The survey asks respondents to give an opinion about the job performance of the current President. Of the 1500 surveys sent out, 480 are returned, and of these, only 120 say they're satisfied with the President's job performance. This is an example of a survey with:
a. little bias because an individual will know for certain whether they approve of the President's job performance.
b. little bias because 1500 voters represent an important part of his district.
c. no bias.
d. None of the answer choices is correct.
2. Surveys, if not done correctly, can lead to seriously biased samples. Which is NOT a bias due to the sampling plan?
a. bias due to selecting a volunteer sample
b. bias due to selecting a convenience sample
c. bias due to nonresponse
d. bias due to selecting a stratified random sample
3. Import customs officials sometimes randomly select crates of cargo for close, but time-consuming, inspection. Suppose there are nine crates of cargo from the following companies, each containing several hundred items. Customs officials will randomly select four for close inspection.
1. Ravenburg
4. Dallhoise
7. Cherryport
2. Corsair
5. Baggate
8. Foxwood
3. Sapphire
6. Strommond
9. Bamboro
To do this, use the numerical labels attached to the previous names and the following list of random digits. Read the list of random digits from left to right, starting at the beginning of the list.
748803 12009 45287 71753 98236 66419 84533 11793 20495 05907 11384
The simple random sample is:
a. 7488.
b. 7483.
c. Cherryport, Dallhoise, Foxwood, and Sapphire.
d. Cherryport, Foxwood, Bamboro, and Strommond.
4. The magazine High Times has a website that once asked visitors whether recreational marijuana use should be legal. This is an example of:
a. voluntary response sampling.
b. a survey with little bias because a large SRS was used.
c. a survey with little bias because someone who responded would know his or her opinion.
d. All of the answer choices are correct.
Explanation / Answer
1. As per the sampling plan, 1500 registered voters were randomly selected, out of which only 480 have responded to the survey. This 480 sample may not be a representative of the registered voters of the community,. That means we have missed out on the opinion of the voters who have not responded and there may be an underlying issue/reason for their non-response. Hence this is a biased sample and any conclusion based on the response from this sample will not represent the opinion of the registered voters in that community.
Ans: d: None of the answer choices is correct.
2. a,b, and d are all directly related to the sampling plan. But c. the non-response bias is not due to the sampling plan as nonresponse could happen even in a carefully selected sample
3. To select 4 crates randomly, we go from left to right of the string of random numbers. We chose one digit random numbers and in case of repetition we discard and pick the next digit in the sequence.
The digits are 748803 12009 .... The first 4 digits are 7488 . We want this sample to be without replacement, that is we want to inspect 4 distinct crates and there is no point in inspecting a crate more than once. So we discard 8 and go for the next number, which is 0. But we do not have a crate numbered 0 in our list, so we move on to the next number in the list which is 3. That means we want to select the crates with labels 7,4,8,3
Ans: c: Cherryport, Dallhoise, Foxwood, and Sapphire.
4. The sample is the visitors to the magazine site who have volunteered to take the survey. Hence this is a voluntary response survey. This sample could be biased as 1. respondents are readers of High Times, 2. Respondents may have strong opinions and hence they are choosing to respond and hence making this a biased sample.
Ans: a. voluntary response sampling.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.