Fractional factorial designs, use

This experiment describes a fractional factorial design used to examine the effects of flame height, flame stoichiometry, acetic acid, lamp current, wavelength, and slit width on the flame atomic absorbance obtained using a solution of 2.00-ppm Ag+. 

Because a fractional factorial design uses less than the complete set of factorial runs, not all of the parameters in the complete model supported by the full factorial can be uniquely estimated. Effect estimates are linked together through aliases. For example, in the 24-1 design in Table 1, the aliases are... 

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