Shows the proportion of defective items.
Shows the number of defective items.
Shows the number of defective items.
Shows the proportion of defective items.
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pcharts display the proportion of nonconforming (defective) items in subgroup samples, which can vary in size. Since each subgroup for a pchart consists of Ni items, and an item is judged as either conforming or nonconforming, the maximum number of nonconforming items in a subgroup is Ni.

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npcharts display the number of nonconforming (defective) items in subgroup samples. Because each subgroup for a npchart consists of Ni items, and an item is judged as either conforming or nonconforming, the maximum number of nonconforming items in subgroup i is Ni.

Note: To use the Sigma column property for P or NP charts, the value needs to be equal to the proportion. JMP calculates the sigma as a function of the proportion and the sample sizes.
LeveyJennings charts show a process mean with control limits based on a longterm sigma. The control limits are placed at 3s distance from the center line. The standard deviation, s, for the LeveyJennings chart is calculated the same way standard deviation is in the Distribution platform.