Case Studies and White Papers


Graphical Selection of Effects in General Factorials

Published: October 2007
Authors: Patrick Whitcomb, Gary Oehlert

This presentation details and demonstrates how to plot effects from general factorials, for example a 3x4x4, on a half-normal plot. This makes selection easy and more precise by it being a graphical method. Previously the half-normal plot of effects, developed by Cuthbert Daniel, was restricted to two-level factorials.

Publication: 2007 Fall Technical Conference

Published: October 2007
Authors: Mark Anderson, Patrick Whitcomb

This article starts with the basics on RSM before introducing two enhancements that focus on robust operating conditions: Modeling the process variance as a function of the input factors and Propagation of error(POE) transmitted from input factor variation. It discusses how to find the find the flats high plateaus for maximum yield and broad valleys that minimize defects. Proceeding from International SEMATECH Manufacturing Initiative (ISMI) Symposium on Manufacturing Effectiveness.

Publication: https://cdnm.statease.com/pubs/RSM_for_peak_performance.pdf

Applicazione di specifiche tecniche DoE per la progettazione di una macchina per il confezionamento di filtri per sigarette

Published: October 2007
Authors: Ivan Eusepi, Marco Righetti

This presentation in Italian details a DOE case study on a filter cigarette packaging machine design using Design-Expert software.

Publication: SixSigmaIn

Published: September 2007
Authors: Steven Peppers, Matt Tiza

This case study details how the Intertape Polymer Group (IPG) used Design of Experiments (DOE) to solve an adhesive tape production problem.

Publication: Adhesives & Sealants Industry

Response Surface Methods for Peak Process Performance

Published: August 2007
Author: Mark Anderson

This is the third article of a series on design of experiments (DOE). The first publication provided tools for process breakthroughs via two-level factorial designs. The second article illustrated how to re-formulate rubbers or plastics using powerful statistical methods for mixture design and analysis. Via two case studies, the author now brings the focus back to process improvement. The key is in-depth DOE aimed at producing statistically-validated predictive models. Response maps made from these models point the way to pinnacles of process performance--sweet spots at high yield of in-specification products made at lowest possible cost.

Publication: Rubber & Plastic News

Published: June 2007
Author: Jeff Hybarger

This article offers 10 tips for avoiding the most common designed experiment mistakes. It is derived from Jeff Hybarger's article in the December 2006 Stat-Teaser newsletter.

Publication: Design Product News

Published: March 2007
Authors: Mark Anderson, Patrick Whitcomb

This article deals with thorny issues that confront every experimenter, i.e., how to handle individual results that do not appear to fit with the rest of the data - damaging outliers and/or a need for transformation. The trick is to maintain a reasonable balance between two types of errors: (1) deleting data that very only due to common causes, thus introducing bias to the conclusions. (2) not detecting true outliers that occur due to special causes. Such outliers can obscure real effects or lead to false conclusions. Furthermore, an opportunity may be lost to learn about preventable causes for failure or reproducible conditions leading to break-through improvements (making discoveries more or less by accident).

Publication: Quality Engineering

Published: January 2007
Author: Richard DeLoach

This article describes a methodological study focused on evaluating the application of MDOE to future operational codes in a rapid and low-cost way to assess the effects of cavity geometry uncertainty.

Publication: Rubber and Plastics News

Published: November 2006
Authors: Mark Anderson, Patrick Whitcomb

This article details the advantages of design of experiments (DOE) over the OFAT (changing only one factor at a time) approach to experimentation. By varying factors at two levels each, but simultaneously rather than one at a time, experimenters can uncover important interactions.

Publication: Chemical Processing

Published: October 2006
Authors: Patrick Whitcomb, Mark Anderson

This mini-paper, provided on pages 5-8 in the publication via the link above*, addresses concerns about mixture designs coming up short on power. *(Manuscript available under Download link below.)

Publication: ASQ Statistics Division Newsletter