Monitoring an Input-Output Model for Production. I. The Control Charts

Control charts are given for monitoring an input-output model against changes in form, against changes in its coefficients, and against changes in process variance. When a process is not in control due to changes in some coefficients, monitoring shifts to a diagnostic mode to identify the altered coefficients and thus the needed adjustments to the process. Control limits from special aid tables are used; these are considered along with the choice of design. Operating characteristics of the charts are summarized under standard assumptions.