1. Chapter 11 Exercise 6 (page 302)A supplier quotes a Cp value of 1.7 After a discussion with representatives you determine that they are calculating standard deviation as you desire but you are concerned that they had a sample size of only 20 Determine a 95% confidence interval for the population Cp
2. Chapter 11 Exercise 7 (page 302) An organization requires a Cp value of 2.00 given a smaple size of 30 determine the min. level for a sampled Cp value in order to be 97.5% confident that the Cp population value is 2.00
3. Data have been collected to test whether the thickness of a poly silicon coating depends upon the deposition temperature. Test whether there is any difference in the thickness at different temperature levels at α = 0.05 (See Table 1).
Table 1
Temperature Polysilicon Thickness
|
1
|
110
|
112
|
109
|
115
|
|
2
|
105
|
99
|
100
|
103
|
|
3
|
115
|
120
|
109
|
117
|
|
4
|
102
|
110
|
108
|
102
|
4. A chemical engineer has reason to believe that the batches of raw materials used in the manufacture of a compound differ significantly in Nitrogen content. Currently the company uses many batches: for this study, the engineer randomly selected five of these batches and recorded 3 observations on each batch. The data is in Table 2. Conduct ANOVA at α = 0.01 and test whether there is any difference
Table - Batches
| 1 |
2 |
3 |
4 |
5 |
| 8.5 |
8.4 |
8.4 |
8.5 |
8.9 |
| 8.6 |
8.5 |
8.9 |
8.4 |
8.6 |
| 8.2 |
8.3 |
8.2 |
8.2 |
8.2 |
5. . Suppose the sample means and standard deviations are observed for the samples of size 5
a. Construct the X bar and s chart.
b. Verify if the process is in control
c. Estimate the population standard deviation
|
Sample
|
X bar
|
s
|
Sample
|
X bar
|
s
|
|
1
|
2.15
|
0.14
|
11
|
2.10
|
0.17
|
|
2
|
2.07
|
0.10
|
12
|
2.19
|
0.13
|
|
3
|
2.10
|
0.11
|
13
|
2.14
|
0.07
|
|
4
|
2.14
|
0.12
|
14
|
2.13
|
0.11
|
|
5
|
2.18
|
0.12
|
15
|
2.14
|
0.11
|
|
6
|
2.11
|
0.12
|
16
|
2.12
|
0.14
|
|
7
|
2.10
|
0.14
|
17
|
2.08
|
0.07
|
|
8
|
2.11
|
0.10
|
18
|
2.18
|
0.10
|
|
9
|
2.06
|
0.09
|
19
|
2.06
|
0.06
|
|
10
|
2.15
|
0.08
|
20
|
2.13
|
0.14
|