Selecting control factor values in a robust design using a scatter plot
Article first published online: 24 SEP 2010
Copyright © 2010 John Wiley & Sons, Ltd.
Quality and Reliability Engineering International
Volume 27, Issue 4, pages 489–497, June 2011
How to Cite
de León, G., Grima, P. and Tort-Martorell, X. (2011), Selecting control factor values in a robust design using a scatter plot. Qual. Reliab. Engng. Int., 27: 489–497. doi: 10.1002/qre.1145
- Issue published online: 23 MAY 2011
- Article first published online: 24 SEP 2010
- robust design;
- variation reduction;
- quality improvement
When the results of an experimental design are analyzed, in which control factors and noise factors are involved, it may be difficult to determine the combination of values of the control factors that produce the best behavior of the response, addressing both its level (or distance from the target value) and its variability. This article presents an analysis proposal that is based on the model obtained for the response and uses, as its central element, a scatter plot of its expected value vs its standard deviation. In this plot, each point corresponds to a combination of values of the control factors; thus, it is easy to identify the points with better response behavior. In our opinion, this graph provides significant advantages over the other methods that have been proposed; among them is the fact that it is always a scatter plot, regardless of the number of factors that end up being active, and that it is easy to understand and use, especially with the possibilities offered by the current statistical software packages. Copyright © 2010 John Wiley & Sons, Ltd.