Monitoring customer complaints using the repetitive sampling

Abstract

A new control chart for a service performance index based upon the proportion of customer complaints using the repetitive sampling scheme is proposed. The control chart coefficients have been estimated for different parametric combinations using different levels of the performance index. The performance of the new control chart is evaluated on the basis of the average run length (ARL) for in-control and shifted processes. A simulation study for estimating three parameters of the proposed control chart is carried out in order to see the performance of the proposed methodology. The proposed control chart performs better than the existing chart in terms of the ARLs. A real-world example from industry has been included for the practical application of the proposed control chart.

Keywords:

• Control charts
• service performance index
• repetitive sampling
• average run length
• standard deviation of run length

Acknowledgments

The author is deeply thankful to the editor and the reviewers for their valuable suggestions to improve the quality of this manuscript. The author, therefore, gratefully acknowledge the DSR technical and financial support.

Additional information

Funding

This work was funded by the Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah, under Grant No. [G:1386-130-1440].