Exercises 17 through 20 refer to the following story: The city of Cleansburg has 8325 registered voters. There is an election for
mayor of Cleansburg, and there are three candidates for the posi-
tion: Smith, Jones, and Brown. The day before the election a tele-
phone poll of 680 randomly chosen registered voters produced the
following results: 306 people surveyed indicated that they would
vote for Smith, 272 indicated that they would vote for Jones and
102 indicated that they would vote for Brown.
17. (a) Describe the population for this survey.
(b) Describe the sample for this survey.
(c) Name the sampling method used for this survey.
18. (a) Give the sampling proportion for this survey.
(b) Give the sample statistic estimating the percentage of
the vote going to Smith.
19. Given that in the actual election Smith received 42% of the
vote, Jones 43% of the vote, and Brown 15% of the vote, find
the sampling errors in the survey expressed as percentages.
20. Do you think that the sampling error in this example was
due primarily to sampling bias or to chance? Explain your
answer.