Gauge imprecision effect on the performance of the &Xmacron;-S control chart

This paper examines the effect of stochastic measurement error (gauge imprecision) on the performance of Shewhart-type &Xmacron;-S control charts. It is shown that gauge imprecision may seriously affect the ability of the chart to detect process disturbances quickly or, depending on the point in time when the error occurs, the probability of erroneously signalling an out-of-control process state.