Chapter 14, Problem 27E

Exercises 25 through 28 refer to the following story: The Cleansburg Planning Department is trying to determine what percent of the people in the city want to spend public funds to revitalize the downtown mall. To do so, the department decides to conduct a survey. Five professional interviewers are hired. Each interviewer is asked to pick a street corner of his or her choice within the city limits, and every day between 4:00 P.M. and 6:00 P.M. the interviewers are supposed to ask each passerby if he or she wishes to respond to a survey sponsored by Cleansburg City Hall. If the response is yes, the follow-up question is asked: Are you in favor of spending public funds to revitalize the downtown mall? The interviewers are asked to return to the same street corner as many days as are necessary until each has conducted a total of 100 interviews. The results of the survey are shown in Table 14-3.

${}^{\text{a}}\text{In favor of spending public funds to revitalize the downtown mall}.$

${}^{\text{b}}\text{Opposed to spending public funds to revitalize the downtown mall}.$

${}^{\text{c}}\text{Declined to be interviewed or had no opinion}.$ Got frustrated and quit.

${}^{\text{d}}\text{Got frustrated and quit}\text{.}$

Interviewer	$Ye{s}^a$	$N{o}^b$	$Nonrespondant{s}^c$
A	35	65	321
B	21	79	208
C	58	42	103
D	78	22	87
$E^{\text{d}}$	12	63	594

a. Can you explain the big difference in the data from interviewer to interviewer?

b. One of the interviewers conducted the interviews at a street corner downtown. Which interviewer? Explain.

c. Do you think the survey was subject to selection bias? Explain.

d. Was the sampling method used in this survey the same as quota sampling? Explain.