2.16 The financial aid advisor of a university plans to use a stratified random sample to estimate the average
amount of money that students spend on textbooks each
term. For each of the following proposed stratification
schemes, discuss whether it would be worthwhile to
stratify the university students in this manner.
a. Strata corresponding to class standing (freshman,
sophomore, junior, senior, graduate student)
b. Strata corresponding to field of study, using the fol-
lowing categories: engineering, architecture, busi-
ness, other
c. Strata corresponding to the first letter of the last
name: A-E, F-K, etc.