Economic and economic-statistical designs of auxiliary information based X¯, synthetic and EWMA charts

Abstract

The economic and economic-statistical performances of auxiliary information based $\overline{X},$ synthetic and EWMA charts in monitoring the mean is investigated. Incorporating the auxiliary characteristic improves the cost and out-of-control run length performances of the charts. As it is often difficult to specify the exact shift size where a quick detection is needed, this paper investigates the economic and economic-statistical performances of auxiliary information based $\overline{X},$ synthetic and EWMA charts, for both cases when the exact shift sizes can and cannot be specified. This is achieved by using the average run length (ARL) and expected average run length (EARL) performance criteria, respectively. The cost performances of these charts are compared and the cost savings are discussed.

Keywords:

• Economic and economic-statistical designs
• Auxiliary information
• Control charts

Acknowledgments

This research is conducted while the corresponding author (Michael B.C. Khoo) is on sabbatical leave at Universiti Tunku Abdul Rahman (UTAR), Kampar.

Additional information

Funding

This research is supported by the MyBrain15 (MyPhD) Scholarship Program under the Ministry of Higher Education, Malaysia.