Chapter 4.2, Problem 66E

To determine

To find out which of the following two plans for randomly assigning the treatments should be the biologist use and explain why.

Answer to Problem 66E

Plan B.

Explanation of Solution

In this study, biologist would like to determine which of the following two brands of weed killer is less likely to harm the plants in a garden at the university. So, two plans were decided for the experiment.

The plan which follows all the three experimental designs principle will be considered for the biologist use. Thus, the three experimental design principles are as:

Control effects of lurking variables and use at least two groups to compare, Randomly assign subjects to each group and Replication.

In this we found out that randomization should be used in an experiment, which was not used in plan A because this plan A only used the healthiest-looking plants. Thus the biologist should use plan B.