DOE Simplified, 3rd Edition

Chapter 12

Practice Experiments

Practice Experiment #1: Breaking Paper Clips

It’s easy to find various brands, sizes, and types (e.g., virgin or recycled, rough-edged or smooth) of paper clips. These can be tested for strength in a simple comparative experiment, such as those illustrated in Chapter 2. (You also might find this to be a good way to relieve stress.) The procedure shown below specifies big versus little paper clips. It’s intended for a group of people, with each individual doing the test. The person-to-person variation should be treated as blocks and removed from the analysis. The procedure is as follows:

1. Randomly select one big and one regular-sized paper clip. Flip a coin to randomly choose the first clip to break: heads = big, ...