In Example 6-2 we found that one of the process variables (B = pressure) was not important. Dropping this variable produces two replicates of a 23 design. The data are shown below:

Assume that C and D are controllable factors and that A is a noise variable.

(a) Fit a model to the mean response.

(b) Fit a model to the In(s²) response.

(c) Find operating conditions that result in the mean filtration rate response exceeding 75 with minimum variance.

(d) Compare your results with those from Example 11-6, which used the transmission of error approach. How similar are the two answers?

Transcribed Image Text:

C D A (+) A (-) s2 45, 48 71, 65 57.75 121.19 68, 80 60, 65 68.25 72.25 43, 45 100, 104 73.00 1124.67 + 75, 70 86, 96 81.75 134.92