THE IMPORTANCE OF OUTCOME DYNAMICS, SIMPLE GEOMETRY AND PRAGMATIC STATISTICAL ARGUMENTS IN EXPOSING DEFICIENCIES OF EXPERIMENTAL-DESIGN STRATEGIES

One-factor-at-a-time experiments and similar ''common sense'' design s trategies continue to be prevalent in industrial experiments in spite of the strong emphasis in statistics courses that these design strateg ies should be avoided. In justifying the avoidance of such design stra tegies, technical criteria such as design efficiency and confounding a re usually stressed, However, these technical criteria routinely are o verlooked by experimenters in industry when the desire for rapid feedb ack on factor effects is given undue precedence, In this article the p reference or rapid feedback over statistical considerations is discuss ed relative to the compelling inherent deficiencies of these designs, The practical difficulties associated with the dynamic nature of the d esign construction, geometric imbalance of the designs, and serious mo deling inadequacies that result om the use of these design strategies are detailed.