The Treatment of Related Experimental Factors by Sliding Levels


Hamada, M.; Wu, C.F.J.   (1995, ASQC)   University of Waterloo, Waterloo, ON; University of Michigan, Ann Arbor, MI

Journal of Quality Technology    Vol. 27    No. 1
QICID: 11399    January 1995    pp. 45-55
List $10.00
Member $5.00

You will need to be signed in.
New to ASQ? Register here.

Article Abstract

Two factors are related when one factor's desirable range depends on the level of another factor. For example, in a chemical reaction, the desirable reaction-time range shifts downward as temperature increases. This is reflected in the experimental design by choosing levels of one factor that depend on the level of the other factor. Taguchi refers to this technique as sliding levels and justifies it by rationales of bad region avoidance and interaction elimination. We explore these rationales and their implications. In particular, we point out problems with Taguchi's analysis strategy which is based on the latter rationale. We propose an alternative analysis method and demonstrate it by reanalyzing three documented experiments; the reanalysis provides new insight about their respective processes. Finally, using the bad region avoidance rationale, we discuss alternative experimental designs.


Regression analysis,Nested experiments,Design of experiments (DOE),Interactions

Browse QIC Articles Chronologically:     Previous Article     Next Article

New Search

Featured advertisers

ASQ is a global community of people passionate about quality, who use the tools, their ideas and expertise to make our world work better. ASQ: The Global Voice of Quality.