Keywords: fractional design, Taguchi design, two-level design, dispersion effects.
This is a highly fractionated two-level factorial design employed as a screening design in an off-line welding experiment performed by the National Railway Corporation of Japan. There were 16 runs and 9 experimental factors. The response variable is the observed tensile strength of the weld, one of several quality characteristics measured. All other variables are at plus and minus levels.
|Rods||Kind of welding rods|
|Drying||Period of drying|
|Strength||Tensile strength of the weld in kg/mm|
Data File (tab-delimited text)
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> jDrying <- jitter(Drying,factor=3) > plot(jDrying,Strength,type="n",xlab="Drying") > points(jDrying[Material==-1],Strength[Material==-1],col=2) > points(jDrying[Material==1],Strength[Material==1],col=4)