Semifolding 2 Designs
نویسندگان
چکیده
This article addresses the varied possibilities for following a two-level fractional factorial with another fractional factorial half the size of the original experiment. While follow-up fractions of the same size as an original experiment are common practice, in many situations a smaller follow-up experiment will suffice. Peter John coined the term “semifolding” to describe using half of a foldover design. Existing literature does include brief mention and examples of semifolding but no thorough development of this followup strategy. After a quick examination of the estimation details for semifolding the 1 IV 2 design, we focus on following 16-run fractions with a semifold design of eight runs. Two such examples are considered one where the initial fraction is resolution IV, the other resolution III. A general result is proven for semifolding p k − IV 2 designs. Conducting full foldover designs in two blocks is also recommended.
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