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 Oneway 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

