Design & Factor Selection
Design Types & Categories
The value of VFR is a guide to the effect caused by removing that run. Runs may be removed because of an unfeasibility of that combination of factor-levels or for convenience. To reduce the size of a design with least negative effect on its performance, the run with the lowest value of VFR should be removed.
Learn more about the DOE tools for designed experiments in Six Sigma Demystified (2011, McGraw-Hill) by Paul Keller, in his online Intro. to DOE short course (only $99) or online Advanced Topics in DOE short course (only $139), or his online Black Belt certification training course ($875).