I am happy to share another answer or two from our statistical consulting team to frequently asked questions (FAQs) about design of experiments (DOE), as well as timely alerts for events, publications, and software updates. Check it out! Feel free to get back to me via mark@statease.com with further questions or comments: I would really appreciate hearing from you!
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Also, see the Stat-Ease blogfor tips on making DOE easy. For example, a recent posting provides insights on "The Importance of Center Points in Central Composite Designs". Take a look!
FAQ
Why does power get calculated for factorial designs but not for response surface methods (RSM)?
Original question from a Principal Scientist: “We noticed that for factorial models the power calculation shows up by default when creating the design. But when creating a central composite design for RSM it does not appear. Why is that?”
Answer from Stat-Ease Consultant Joe Carriere:
“Power isn’t included on the build screens because we recommend using fraction of design space (FDS) for sizing and evaluating response surface designs, not power. Assuming you know the vital few factors at this optimization stage, the goal for RSM shifts from effect detection to modeling the responses within a desired precision.
“Also view this presentation by my colleague Shari Kraber on using precision to size response surfaces. She details FDS and demonstrates how to apply this tool using Stat-Ease software to size an RSM, as well mixture designs for optimal formulation.”
PS Do you need a speaker on DOE for a 2023 learning session within your company or professional society at regional, national, or international levels? If so, please get back to me. – Mark
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Shari Kraber wrote the DOE portion of Chapter 48–Quality Planning & Design for the new 6th edition of Maynard's Industrial and Systems Engineering Handbook published by McGraw-Hill. They provide details on the book and availability for purchase here.
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