Table 1 Plackett–Burman design matrix represents the coded values of five independent variables and the absorbance readings at 420 nm as a response reflecting the AgNPs concentration
Trials | A | B | C | D | E | Responses | |
|---|---|---|---|---|---|---|---|
Actual* | Predicted | ||||||
1 |  + 1 | −1 | −1 |  + 1 | −1 | 0.442 | 0.434 |
2 |  + 1 |  + 1 | −1 | −1 |  + 1 | 2.199 | 2.081 |
3 |  + 1 |  + 1 |  + 1 | −1 | −1 | 1.098 | 1.216 |
4 | −1 |  + 1 |  + 1 |  + 1 | −1 | 0.302 | 0.184 |
5 |  + 1 | −1 |  + 1 |  + 1 |  + 1 | 1.523 | 1.531 |
6 | −1 |  + 1 | −1 |  + 1 |  + 1 | 0.931 | 1.049 |
7 | −1 | −1 |  + 1 | −1 |  + 1 | 1.192 | 1.184 |
8 | −1 | −1 | −1 | −1 | −1 | 0.079 | 0.087 |