Evaluating multi-objective economic-statistical design of attribute C control charts for monitoring the number of non-conformities

The C control chart is mostly used to monitor the number of non-conformities per inspection unit of constant size. It is known that the classic C-chart control limits often experience a high false alarm rate and thus lead to the increase of unnecessary costs of inspection. Among many works performed to improve C-charts, this paper presents the optimised control limits approach to the C-chart. In addition, different C-charts are evaluated through factors related to the design of the control chart. Optimally selecting design parameters depends on several process parameters from statistical and/or economic aspects in the literature. This study presents multi-objective economic-statistical design of different C control charts under single assignable cause. An algorithm using the data envelopment analysis (DEA) is employed to solve the models. A numerical example is used to illustrate the algorithm procedure and to evaluate the performances of different designs.