1. Researchers at a weight loss clinic are conducting an experiment to determine whether weighing oneself daily does in fact lead to greater weight loss while on a diet, as is commonly assumed. They plan to compare the percentage of total body weight lost after twelve weeks on the clinic's diet plan for two groups of people, one weighing themselves every day and one not weighing themselves while on the diet. Eight volunteers that are just beginning the weight loss program are available to participate in this study. For each of these volunteers (numbered 1 through 8), the weight loss clinic collected information on the method by which the volunteer heard about the weight loss program and whether or not the volunteer is going to exercise while on the diet plan. This information is presented in the table below. Based upon this information, the researchers have decided to incorporate blocking into their experimental design.

Volunteer

Method

Exercise

1

TV commercial

Yes

2

On-line Ad

No

3

On-line Ad

Yes

4

TV commercial

Yes

5

On-line Ad

Yes

6

On-line Ad

No

7

TV commercial

No

8

TV commercial

No

1. Identify (by number) the volunteers that you would group into blocks. Justify your choice of blocks.