PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
1. The following table shows the measurements of the length of a manufactured
plastic part before and after been submitted to a thermal process.
Part Before Thermal P. After Thermal P. Difference
1 10.49 9.11 1.38
2 16.62 13.25 3.37
3 17.30 14.72 2.58
4 15.48 12.74 2.74
5 12.97 10.12 2.85
6 17.26 14.57 2.69
7 13.40 11.22 2.18
8 13.90 11.10 2.8
9 13.63 11.42 2.21
10 13.26 10.91 2.35
11 14.37 12.11 2.26
12 11.70 8.62 3.08
13 15.47 12.59 2.88
14 17.84 15.09 2.75
15 14.07 10.55 3.52
- Construct a boxplot for both treatments (before and after). Discuss the plots.
- Is the thermal process affecting the mean length of the plastic part?
- What change in the part length could be detected by this test if we use a
confidence level of 95% and a power of 90%? Would you increase your
sample size?
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
Prueba Pareada
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
Análisis de Tamaño de Muestra
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
2. In a study performed, Machine A produces 56 of 200 parts with non-acceptable
aesthetics characteristics, Machine B produced 29 of 150 parts that were
rejectable due to the same characteristics.
- Can we conclude that there is significant difference in the rejection rate of the
two machines?
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
3. The pH of a solution is an important characteristic of a process being studied.
There is a claim that the average pH produced in the solution is 6.5. Nine
prepared solution were observed rendering the following results: 7.3, 6.5, 6.4, 6.1,
6.0, 6.5, 6.2, 5.8, 6.7.
- Do these readings cast doubt upon the claimed average.
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
4. Is the normal probabilistic model reasonable for the following 20 observations? If,
so, estimate the probability of having a random observation between 20 and 28.
27.29 24.78 24.01 24.26 27.51 25.72 24.51 26.51 27.07 23.41
25.76 26.43 20.84 22.65 27.93 24.16 24.57 22.85 21.66 24.21
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
5. Four laboratories are being used to perform chemical analyses. Samples of the
same material are sent to the laboratories for analysis as part of the study to
determine whether or not the give on the average the same results. The analytical
results for the four laboratories are as follows:
Laboratory
A B C D
58.7 62.7 55.9 60.7
61.4 64.5 56.1 60.3
60.9 63.1 57.3 60.9
59.1 59.2 55.2 61.4
58.2 60.3 58.1 62.3
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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PRACTICE EXERCISES FOR STRYKER
MINITAB SEMINAR
David R. González Barreto Stryker, Arroyo Puerto Rico
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