MACHART Statement: MACONTROL Procedure
Overview: MACHART Statement
The MACHART statement creates a uniformly weighted moving average control chart (commonly referred to as a moving average control chart), which is used to decide whether a process is in a state of statistical control and to detect shifts in the process average.
You can use options in the MACHART statement to
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specify the span of the moving averages (the number of terms in the moving average)
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compute control limits from the data based on a multiple of the standard error of the plotted moving averages or as probability limits
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tabulate the moving averages, subgroup sample sizes, subgroup means, subgroup standard deviations, control limits, and other information
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save control limit parameters in an output data set
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save the moving averages, subgroup sample sizes, subgroup means, and subgroup standard deviations in an output data set
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read control limit parameters from an input data set
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specify one of several methods for estimating the process standard deviation
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specify a known (standard) process mean and standard deviation for computing control limits
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display a secondary chart that plots a time trend that has been removed from the data
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add block legends and symbol markers to reveal stratification in process data
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superimpose stars at points to represent related multivariate factors
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clip extreme points to make the chart more readable
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display vertical and horizontal reference lines
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control axis values and labels
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control layout and appearance of the chart
You have three alternatives for producing moving averge control charts with the MACHART statement:
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ODS Graphics output is produced if ODS Graphics is enabled, for example by specifying the ODS GRAPHICS ON statement prior to the PROC statement.
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Otherwise, traditional graphics are produced by default if SAS/GRAPH® is licensed.
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Legacy line printer charts are produced when you specify the LINEPRINTER option in the PROC statement.
See Chapter 3: SAS/QC Graphics, for more information about producing these different kinds of graphs.