3.
Production
Process Characterization
3.5.
Case Studies
3.5.2.
Machine Screw Case Study
|
Summary of Throughput
|
The throughput is summarized in the following table (this
was part of the original data collection, not the result of
analysis).
Machine
|
Day 1
|
Day 2
|
Day 3
|
1
|
576
|
604
|
583
|
2
|
657
|
604
|
586
|
3
|
510
|
546
|
571
|
This table shows that machine 3 had significantly lower
throughput.
|
Graphical Representation of Throughput
|
We can show the throughput graphically.
The graph clearly shows the lower throughput for machine 3.
|
Analysis of Variance for Throughput
|
We can confirm the statistical significance of the lower throughput
of machine 3 by running an analysis of variance.
Source DF Sum of Mean F Statistic Prob > F
Squares Square
-------------------------------------------------------------------
Machine 2 8216.89 4108.45 4.9007 0.0547
Residual 6 5030.00 838.33
-------------------------------------------------------------------
Corrected Total 8 13246.89 1655.86
|
Interpretation of ANOVA Output
|
We summarize the level means for machine 3 in the following table.
Machine 3 Level Means for One-way ANOVA
Level
|
Number
|
Mean
|
Standard Error
|
Lower 95% CI
|
Upper 95% CI
|
1
|
3
|
587.667
|
16.717
|
546.76
|
628.57
|
2
|
3
|
615.667
|
16.717
|
574.76
|
656.57
|
3
|
3
|
542.33
|
16.717
|
501.43
|
583.24
|
|