Note: See Median and Range Charts Examples in the SAS/QC Sample Library.
In this example, the MRCHART statement is used to create a summary data set that can be read later by the SHEWHART procedure
(as in the preceding example). The following statements read measurements from the data set Detergent
and create a summary data set named Dethist
:
proc shewhart data=Detergent; mrchart Weight*Lot / outhistory = Dethist nochart; run;
The OUTHISTORY= option names the output data set, and the NOCHART option suppresses the display of the charts, which would be identical to the charts in Figure 17.43. Options such as OUTHISTORY= and NOCHART are specified after the slash (/) in the MRCHART statement. A complete list of options is presented in the section Syntax: MRCHART Statement.
Figure 17.46 contains a partial listing of Dethist
.
Figure 17.46: The Summary Data Set Dethist
Summary Data Set DETHIST for Detergent Box Weights |
Lot | WeightM | WeightR | WeightN |
---|---|---|---|
1 | 22.56 | 9.54 | 5 |
2 | 23.54 | 3.07 | 5 |
3 | 24.35 | 4.65 | 5 |
4 | 25.52 | 5.05 | 5 |
5 | 23.25 | 8.04 | 5 |
There are four variables in the data set Dethist
.
Lot
contains the subgroup index.
WeightM
contains the subgroup medians.
WeightR
contains the subgroup ranges.
WeightN
contains the subgroup sample sizes.
Note that the summary statistic variables are named by adding the suffix characters M, R, and N to the process Weight
specified in the MRCHART statement. In other words, the variable naming convention for OUTHISTORY= data sets is the same
as that for HISTORY= data sets.
For more information, see OUTHISTORY= Data Set.