a. A set of data is at the nominal level of measurement and you want to obtain a representative data value. Which of the following is most appropriate: mean, median, mode, or midrange? Why?
b. A sample is obtained by telephoning the first 250 people listed in the local telephone directory. What type of sampling (random, stratified, systematic, cluster, convenience) is being used?
c. An exit poll is conducted by surveying everyone who leaves the polling booth at 30 randomly selected election ridings. What type of sampling (random, stratified, systematic, cluster, convenience) is being used?