Quality and Reliability Methods - SAS

Chapter 7 Multivariate Control Charts 109
Launch the Platform
Launch the Platform
To generate a multivariate control chart, select Analyze > Quality And Process > Control Chart >
Multivariate Control Chart.
Figure 7.2 Multivariate Control Chart Launch Window
Y, Columns are the columns to be analyzed.
Subgroup
is a column that specifies group membership. Hierarchically, this group is within Group.
Group is a column that specifies group membership at the highest hierarchical level.
In addition, there is a Get Targets button that enables you to pick a JMP table that contains historical
targets for the process.
Control Chart Usage
There are two distinct phases in generating a multivariate control chart. Phase 1 is the use of the charts for
establishing control. Historical limits are set in this stage, and initial tests show whether the process is in
statistical control. The objective of phase 1 is to obtain an in-control set of observations so that control
limits can be set for phase 2, which is the monitoring of future production.
Phase 1—Obtaining Targets
To illustrate the process of creating a multivariate control chart, we use data collected on steam turbines,
taken from Mason and Young (2002). Historical data, stored in Steam Turbine Historical.jmp, and found
in the Quality Control subfolder, is used to construct the initial chart.
Launch the platform and assign all continuous variables to the Y, Columns role. When you click OK,
Figure 7.3 appears.