24 In each of the following situations, evaluate whether the method of sample selection is appropriate for obtaining information about the population of interest How would you improve the sample design?

a) A newspaper wants to determine whether its readers believe that governincnt expendi- tures should be reduced by cutting welfare programs. They provide a telephone number for readers to call to give their opinions Based on 1434 calls that they receive, they report that 93% of the city's residents believe that welfare payments should hc reduced bi A congresswoman reports that letters to her office are running 3 to 1 in opposiuon to the passage of stricter gun control laws. She concludes that approximately 75% of her constituents oppose stricter gun control laws

c) An anthropology professor wanted to compare attitudes toward premantal sex of phys- ical science majors and social science majors She administered a questionnaire to her large class of Anthropology 437, Comparative Human Sexuality She found no apprecia- bic difference between her physical science and social science majors in their attitudes, so she concluded that the two student groups were about the same in their relative accep tance of premarital sex.

d) A questionnaire was mailed to a simple random sample of 500 household addresses in a city Ten were ictured as bad addresses. 63 were returned completed, and the rest were not returned The researcher analyzed the 63 cases and reported that they represent a random sample of city households."