3. Production Process Characterization
3.5. Case Studies
3.5.2. Machine Screw Case Study

## Throughput

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.

 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