Analyzing DOE With Statistical Software Packages: Controversies and Proposals

Abstract

This article studies and evaluates how five well-known statistical packages—JMP, Minitab, SigmaXL, Statgraphics, and Statistica—address the problem of analyzing the significance of effects in unreplicated factorial designs. All five use different methods and criteria that deliver different results, even for simple textbook examples. The article shows that some of the methods used are clearly incorrect and deliver incorrect results. Finally, it raises the question of the impact that this may have in hindering the use of design of experiments (DOE) by nonexpert practitioners, and it provides suggestions for making this analysis more effective and easier to understand. Supplementary materials for this article are available online.

• Factorial design
• Industrial experimentation
• Lenth method
• Significance of effects.