Improving Taguchi's Packaging of Fractional Factorial Designs

Two changes to Taguchi's packaging of fractional factorial designs are suggested. First, Tsui's idea of confounding tables is supported. Second, a modification of Taguchi's linear graphs is proposed in which the way vertices and lines are drawn indicates whether the main effects and interactions corresponding to those vertices and lines are confounded with other two-factor interactions. This modification tends to encourage the use of a different set of linear graphs and thereby to encourage the use of higher resolution designs.