There are two primary scenarios for using the MVP procedures:
To determine whether a process is stable, you can construct and SPE charts from an existing set of process measurements (this is referred to as a Phase I analysis). First, build a principal component model with the MVPMODEL procedure, saving the measurements and the computed observationwise statistics (including and SPE) in an OUT= data set. Then specify this data set as a HISTORY= input data set for the MVPMONITOR procedure to create and SPE charts. Contribution plots indicate which of the original variables are involved in unusual variation displayed by the and SPE charts. Follow-up action might be needed to adjust the process and eliminate unusual variation signaled by the charts.
To detect changes in a stable process, you can construct and SPE charts from newly acquired data by using the principal component model developed from previous data (this is referred to as a Phase II analysis). You can save information about the model in the OUTLOADINGS= data set created by the MVPMODEL procedure. Specify this data set as a LOADINGS= input data set and specify the new data as a DATA= input data set to create and SPE charts with the MVPMONITOR procedure.