Comment on the following sampling designs:
a. A citizen’s group interested in generating public and financial support for a new university basketball arena prints a questionnaire in area newspapers. Readers return the questionnaires by mail.
b. A department store that wishes to examine whether it is losing or gaining customers draws a sample from its list of credit card holders by selecting every tenth name.
c. A motorcycle manufacturer decides to research consumer characteristics by sending one hundred questionnaires to each of its dealers. The dealers will then use their sales records to track down buyers of this brand of motorcycle and distribute the questionnaires.
d. An advertising executive suggests that advertising effectiveness be tested in the real world. A one-page ad is placed in a magazine. One-half of the space is used for the ad itself. On the other half, a short questionnaire requests that readers comment on the ad. An incentive will be given for the first thousand responses.
e. A research company obtains a sample for a focus group through organized groups such as church groups, clubs, and schools. The organizations are paid for securing respondents; no individual is directly compensated.
f. A researcher suggests replacing a consumer diary panel with a sample of customers who regularly shop at a supermarket that uses optical scanning equipment. The burden of recording purchases by humans will be replaced by computerized longitudinal data.
g. A banner ad on a business-oriented Web site reads, “Are you a large company Sr. Executive? Qualified execs receive $50 for less than 10 minutes of time. Take the survey now!” Is this an appropriate way to select a sample of business executives?