A recent investigation studied the effects of levels of several vitamins in a cell culture on the yield (g/L) of pyruvate, a useful organic acid. The data in the following table are presented as two replicates of a 23 design. The factors are A, nicotinic acid, B, thiamine, and C, biotin.
|
A
|
B
|
C
|
Yields
|
Mean Yield
|
|
-1
|
-1
|
-1
|
0.55
|
0.49
|
0.520
|
|
1
|
-1
|
-1
|
0.60
|
0.42
|
0.510
|
|
-1
|
1
|
-1
|
0.37
|
0.28
|
0.325
|
|
1
|
1
|
-1
|
0.30
|
0.28
|
0.290
|
|
-1
|
-1
|
1
|
0.54
|
0.54
|
0.540
|
|
1
|
-1
|
1
|
0.54
|
0.47
|
0.505
|
|
-1
|
1
|
1
|
0.44
|
0.33
|
0.385
|
|
1
|
1
|
1
|
0.36
|
0.20
|
0.280
|
a) Compute estimates of the main effects and interactions.
b) Rank the effects and comment on their relative importance.