Twenty-one daily responses of stack loss (y) (the amount ofammonia escaping) were measured with air flow x1, temperature x2,and acid concentration x3.
- Check the significance of the model using ANOVA via Minitab andstate your conclusion at 5% alpha level. [5 marks]
Using stepwise method, find the best regression model by Minitaband explain the results obtained at each step. [3 marks]
| y | x1 | x2 | x3 |
42 | 80 | 27 | 89 |
37 | 80 | 27 | 88 |
37 | 75 | 25 | 90 |
28 | 62 | 24 | 87 |
18 | 62 | 22 | 87 |
18 | 62 | 23 | 87 |
19 | 62 | 24 | 93 |
20 | 62 | 24 | 93 |
15 | 58 | 23 | 87 |
14 | 58 | 18 | 80 |
14 | 58 | 18 | 89 |
13 | 58 | 17 | 88 |
11 | 58 | 18 | 82 |
12 | 58 | 19 | 93 |
8 | 50 | 18 | 89 |
7 | 50 | 18 | 86 |
8 | 50 | 19 | 72 |
8 | 50 | 19 | 79 |
9 | 50 | 20 | 80 |
15 | 56 | 20 | 82 |
15 | 70 | 20 | 91 |
