This example uses the Socket Thickness.jmp sample data table, which includes measurements for the thickness of sockets. There has been an increase in the number of defects during production and you want to investigate why this is occurring. Use Control Chart Builder to investigate the variability in the data and the control of the process.
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Select Analyze > Quality and Process > Control Chart Builder.

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Xcharts display subgroup means (averages)

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Rcharts display subgroup ranges (maximum – minimum)

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Scharts display subgroup standard deviations

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.
The CCB makes a few decisions for you based on the variable selected. For example, if there is no X variable, a cchart is originally created because there is no way to estimate the binomial distributions. Upon adding an X variable (or lot size), the platform switches to a npchart if the count per subgroup is less than the subgroup sample size. Once the basic chart is created, you can use the menus and other options to change the type, the statistic, and the format of the chart.
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pcharts display the proportion of nonconforming (defective) items in subgroup samples, which can vary in size. Because 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.

The most common control charts are available in the Control Chart Builder and in the Control Chart platform. Use the Control Chart Builder as your first choice to easily and quickly generate charts. JMP automatically chooses the appropriate chart type based on the data. Control Chart Types summarizes the different control chart types.