Cindy Ho, VP of Finance at Discrete Components, Inc. (DCI), theorizes that the
discount level offered to credit customers affects the average collection period on credit
sales. Accordingly, she has designed an experiment to test her theory using four sales
discount rates (0%, 2%, 4%, and 6%). Cindy wants to control for the size of the
customer but not to test for it as the main variable of interest so she classified DCI’s
credit customers into three categories by total assets (small, medium, and large). Then,
she randomly assigned four customers from each category to a sales discount rate.
Cindy’s experimental design is a ________.
a) normalized block design
b) completely randomized design
c) factorial design
d) random block design
e) partially randomized design
Which of the following tests should be used to compare the means of two populations if
the samples are independent?
a) Mann-Whitney test
b) Wilcoxon test
c) Runs test
d) Spearman’s test
e) Kruskal-Wallis test