EPA regulates the level of CO2 emissions. Recently, the EPAbegan applying an automated control chart methodology to detectundermeasurement of emissions data. The three daily samples of CO2levels for each of 15 days are shown in the below table.
a. Construct two control charts for the daily average andvariation of CO2 levels.
b. Based on the control chart, describe the behavior of themeasurement process.
1 | 12.9 | 12.1 | 13.8 |
2 | 13.2 | 13.2 | 12.7 |
3 | 13.3 | 13.5 | 13.5 |
4 | 13.1 | 12.2 | 12.3 |
5 | 13.2 | 13.2 | 12.5 |
6 | 13 | 13 | 12.9 |
7 | 12.5 | 13.8 | 13.2 |
8 | 12.7 | 13.4 | 13 |
9 | 12.8 | 12.7 | 13.6 |
10 | 12.7 | 12.9 | 13.4 |
11 | 12.9 | 12 | 13.3 |
12 | 12 | 13.7 | 13.1 |
13 | 12.9 | 13.1 | 13 |
14 | 12.8 | 13.6 | 13.3 |
15 | 12.7 | 13.6 | 13.2 |
