A Messy, but Instructive, Case Study in Design of Experiments

A company manufacturing fans wished to conduct an experimental design to determine the best combination of three factors affecting the breaking torque of the fans. Analysis of the data ceased to be straightforward when the authors found that the data failed the test for homogeneity of variances. After unsuccessfully attempting to transform the data and thereby meet the assumptions necessary to carry on the analysis, the authors relied upon a graphical analysis and a careful study of the means for each design point. This paper describes a statistically sound but novel strategy used to complete the analysis

An Experiential Approach to Integrating ANOVA Concepts

This article, created by authors Belva J. Cooley and LeRoy A. Franklin, respectively from the Rose-Hulman Institute of Technology and the University of Montana, presents a dataset based on an industrial case study using design of experiments. It can be used to discuss sample size, power, statistical significance, interaction terms, type I and type II errors, the role and importance of the error term, design of experiments, and analysis of variance. This is a great introduction to ANOVA testing