CHECK THE BASICS

For Exercise 4.1, see page 72; for Exercise 4.2, see page 75.

Question 4.3

4.3 What does the margin of error include? When a margin of error is reported for a survey, it includes

  1. (a) random sampling error and other practical difficulties like undercoverage and nonresponse.

  2. (b) random sampling error, but not other practical difficulties like undercoverage and nonresponse.

  3. (c) practical difficulties like undercoverage and nonresponse, but not random sampling error.

  4. (d) None of the above is correct.

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Question 4.4

4.4 What kind of sample? Archaeologists plan to examine a sample of two-meter-square plots near an ancient Greek city for artifacts visible in the ground. They choose separate samples of plots from floodplain, coast, foothills, and high hills. What kind of sample is this?

  1. (a) A simple random sample

  2. (b) A voluntary response sample

  3. (c) A stratified sample

  4. (d) A cluster sample

Question 4.5

4.5 Sampling issues. A sample of households in a community is selected at random from the telephone directory. In this community, 4% of households have no telephone, 10% have only cell phones, and another 25% have unlisted telephone numbers. The sample will certainly suffer from

  1. (a) nonresponse.

  2. (b) undercoverage.

  3. (c) false responses.

  4. (d) all of the above.

Question 4.6

4.6 Question wording. Which of the following represents wording that will most likely not influence the answers?

  1. (a) Do you think that all instances of academic misconduct should be reported to the dean?

  2. (b) Academic misconduct undermines the integrity of the university and education in general. Do you believe that all instances of academic misconduct should be reported to the dean?

  3. (c) Academic misconduct can range from something as minor as using one’s own work in two courses to major issues like cheating on exams and plagiarizing. Do you believe that all instances of academic misconduct should be reported to the dean?

  4. (d) None of the above will influence the answers.

Question 4.7

4.7 Sampling considerations. A statistics class has 10 graduate students and 40 undergraduate students. You want to randomly sample 10% of the students in the class. One graduate student and four undergraduate students are selected at random. Which of the following is not correct?

  1. (a) Because each student has a 10% chance of being selected, this is a simple random sample.

  2. (b) Because each sample includes exactly one graduate student and four undergraduate students, this is not a random sample.

  3. (c) It is possible to get a sample that contains only graduate students.

  4. (d) It is possible to get a sample that contains only undergraduate students.