The extent to which products meet specifications needs to be systematically monitored in a production process. Product quality will typically be defined by two quantities: deviations from stated ...

In this paper we derive the operating characteristic of the control chart for sample means when process standards are unspecified. Under the null hypothesis the distribution of the process is N(μ, σ2) ...

There is considerable disagreement on how to handle autocorrelation in process data. Consider the following three views: At one extreme, Wheeler (1991b) argues that the usual control limits are ...

SPC is a statistical tool that objectively identifies when it is worthwhile to perform a formal investigation of manufacturing variation, in order to identify and reduce its cause. SPC continually ...

The Christie NHS Foundation Trust in Manchester has implemented visualisation software on statistical process control (SPC) charts to improve clinical outcomes. The Christie is Europe’s largest single ...

Overlay control based on DI metrology of optical targets has been the primary basis for run-to-run process control for many years. In previous work we described a scenario where optical overlay ...

To enable efficient monitoring systems, life-science companies need to effectively apply run rules. To maintain a state of control and comply with regulatory authorities, many pharmaceutical, biotech, ...