For information on the methods used to create the U chart, go to Methods and formulas for U Chart.
The number of plot points equals the number of samples in your study.
The cumulative DPU for the jth sample is calculated as follows:
The reference lines on the plot are calculated as follows:
For more information on the confidence bounds, go to Methods and formulas for confidence intervals and bounds in Poisson Capability Analysis.
Term | Description |
---|---|
Di | Number of defectives in the ith sample |
Ni | The ith sample size |