More on Design of Experiments
Experiment, and it will lead you to the light.
Chapter 7 discussed the use of statistically designed experiments to collect data for building models, focusing on experiments involving three variables. As you use this approach, you may encounter situations in which you have four or more variables to study. This appendix presents some designs that enable you to investigate the effects of four or more variables and provides guidance on how to analyze the results. The designs discussed are summarized in Table E.1 and shown in detail in Tables E.2 to E.7. The references at the end of this appendix present further details on the use and analysis of these designs.
Table E.1 shows the number of variables that each design ...