Choosing Subgroup Size on the Basis of Control Chart Sensitivity for X-Bar Charts – Paper Appearing in Fall 1985 Newsletter

Abstract: For a given shift size between two processes, the probability of detecting this shift increases with increasing sample size (n). The analogous is also true. Therefore, in the early history of a process, larger subgroups with higher sensitivities may be desired, but normally smaller subgroups may be chosen to avoid needless adjustments or investigations when shifts of relatively small magnitude occur.

Keywords: X-bar Chart - Sensitivity analysis - Control limits - Subgroup Size