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McCaryille & Montgomery
This also can be described pictorially as shown in Figurę 9. When three gages are employed, the defect level is
P(goodjreject) = J[fCz)Jg‘, (w)dwjg'2(x)dxjg'3(y)dy]dz (10)
USL z z z
This system is illustrated in Figurę 10.
By utilizing Equation (10), a test engineer can determine the guard bands for a three gage system such that an acceptable defect level is maintained. However, an infinite combination of guard bands can be used to achieve this outcome. Naturally, the engineer will want to choose the guardbands that would accomplish thecorporate and customer defect level