A simple spatial analysis of restaurants in Duluth, Ga

This analysis applies Statistical Process Control (SPC) techniques to monitor semiconductor resistivity measurements. Retrospective Phase I analysis identified and excluded two special-cause subgroups (6 and 16) to establish stable control limits. Using these limits, Phase II online monitoring showed all subgroups in control with no evidence of mean or dispersion shifts. The study highlights the importance of identifying assignable causes, maintaining stable processes, and continuing routine SPC for process reliability.