An article in the Sacramento Bee (12 January 1998, p. A4) was titled “ College freshmen show conservative side” and reported the results of a fall 1997 survey “ based on responses from a representative sample of 252,082 full-time freshmen at 464 two- and four- year colleges and universities nationwide.” The article did not explain how the schools or students were selected.
a. For this survey, explain what a unit is, what the population is, and what the sample is.
b. Assuming a random sample of students was selected at each of the 464 schools, what type of sample was used in this survey? Explain.