Chapter 13, Problem 46E

To determine

To explain the randomization in design.

Explanation of Solution

There might be bias in the results or in the subjects. Therefore, to reduce this bias and equalize groups with respect to unknown factor we need randomization. This experiment has 2 factors like water temperature and wash cycle. Each factor having 2 levels. Water temperature has hot and cold levels. Wash cycle has regular and delicate levels. Therefore, it creates 4 treatments. The find 32 shirts and randomly assign 8 shirts to each treatment group. Wash the shirts and rate for cleanliness. Finally, compare the level of cleanliness in each group. In this experiment, randomization is important because it will reduce the variability in the result.