Table 4.
Central composite design matrix of variables
| Run | Coded values | Actual values | ||||||
|---|---|---|---|---|---|---|---|---|
| A | B | C | D | A | B | C | D | |
| 1 | −1 | −1 | 1 | 1 | 10 | 24 | 20 | 60 |
| 2 | 1 | −1 | −1 | −1 | 15 | 24 | 10 | 40 |
| 3 | −1 | 1 | 1 | −1 | 10 | 60 | 20 | 40 |
| 4 | 0 | 0 | 0 | 0 | 12.5 | 42 | 15 | 50 |
| 5 | −1 | 1 | 1 | 1 | 10 | 60 | 20 | 60 |
| 6 | −1 | −1 | −1 | 1 | 10 | 24 | 10 | 60 |
| 7 | 0 | 0 | 0 | 0 | 12.5 | 42 | 15 | 50 |
| 8 | 1 | −1 | 1 | 1 | 15 | 24 | 20 | 60 |
| 9 | 0 | 0 | 0 | 0 | 12.5 | 42 | 15 | 50 |
| 10 | 0 | 0 | 0 | −2 | 12.5 | 42 | 15 | 30 |
| 11 | 0 | 2 | 0 | 0 | 12.5 | 78 | 15 | 50 |
| 12 | −1 | −1 | −1 | −1 | 10 | 24 | 10 | 40 |
| 13 | 1 | 1 | 1 | 1 | 15 | 60 | 20 | 60 |
| 14 | 0 | 0 | −2 | 0 | 12.5 | 42 | 5 | 50 |
| 15 | −1 | −1 | 1 | −1 | 10 | 24 | 20 | 40 |
| 16 | 1 | 1 | −1 | −1 | 15 | 60 | 10 | 40 |
| 17 | 0 | 0 | 0 | 2 | 12.5 | 42 | 15 | 70 |
| 18 | −1 | 1 | −1 | 1 | 10 | 60 | 10 | 60 |
| 19 | 1 | 1 | 1 | −1 | 15 | 60 | 20 | 40 |
| 20 | 1 | −1 | 1 | −1 | 15 | 24 | 20 | 40 |
| 21 | 2 | 0 | 0 | 0 | 17.5 | 42 | 15 | 50 |
| 22 | −1 | 1 | −1 | −1 | 10 | 60 | 10 | 40 |
| 23 | 1 | −1 | −1 | 1 | 15 | 24 | 10 | 60 |
| 24 | 1 | 1 | −1 | 1 | 15 | 60 | 10 | 60 |
| 25 | 0 | 0 | 2 | 0 | 12.5 | 42 | 25 | 50 |
| 26 | 0 | −2 | 0 | 0 | 12.5 | 6 | 15 | 50 |
| 27 | −2 | 0 | 0 | 0 | 7.5 | 42 | 15 | 50 |